---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 10/15/17: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:19 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) 2. 05:31 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Charlie England) 3. 05:42 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) 4. 08:23 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Robert L. Nuckolls, III) 5. 08:38 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) 6. 08:51 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Charlie England) 7. 09:12 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) 8. 10:28 AM - Re: Re: Constructing an automatic RCA video camera feed splitter (Bill) 9. 12:19 PM - Re: Re: Constructing an automatic RCA video camera feed splitter (Robert L. Nuckolls, III) 10. 12:34 PM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) 11. 01:06 PM - Re: Re: Constructing an automatic RCA video camera feed splitter (Paul A. Fisher) 12. 08:01 PM - Re: Constructing an automatic RCA video camera feed splitter (Eric Page) 13. 08:07 PM - Re: Constructing an automatic RCA video camera feed splitter (Eric Page) 14. 08:44 PM - Re: Re: Constructing an automatic RCA video camera feed splitter (Alec Myers) ________________________________ Message 1 _____________________________________ Time: 05:19:39 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter Another possible gotcha: The AD8184 doesnt do any kind of video buffering, and the various video sources are not frame-locked. (In this scenario there is no 60Hz ac for the camera to sync to). So what the effect of switching sources will be is uncertain. Depending on the video display it could be anything from an unnoticeable half frame glitch to several seconds of rolling display before it locks into the new frame source. Its definitely worth experimenting before settling on the final parts list. On Oct 15, 2017, at 00:43, Alec Myers wrote: If you use a PIC, you could (trivially) do the following: Hold the button down for ten seconds to enter programming mode. Press the button briefly x times to set the scan period at x seconds. Press the button for two seconds to exit programming mode. No need for resistors at all. > On Oct 14, 2017, at 8:38 PM, Eric Page wrote: > > > Wade, > > Question: do you want to be able to adjust the scan rate as a matter of routine operation (i.e. with a panel-mounted knob), or do you envision setting the rate where you like it at installation, and leaving it alone? > > The answer will dictate whether we put a small trimmer potentiometer on the circuit board or design for a larger panel-mounted potentiometer and knob. > > Eric > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=473556#473556 > > > > > > > > > ________________________________ Message 2 _____________________________________ Time: 05:31:39 AM PST US From: Charlie England Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter That stuff is cool as far as programming tricks go, but who will be able to use the hardware except the original designer? I, and everyone else on this list, have owned dozens of electronic gadgets over the years that are absolutely impossible to set up and use without the English-as-a-second-language printed manual that you can't find after the 1st month of ownership. I have to use google on my desktop to explore how to get my phone apps to work like I want. Just something to consider, when designing for general use instead specifically trained fighter pilots or astronauts. On Sat, Oct 14, 2017 at 11:43 PM, Alec Myers wrote: > > If you use a PIC, you could (trivially) do the following: > > Hold the button down for ten seconds to enter programming mode. Press the > button briefly x times to set the scan period at x seconds. Press the > button for two seconds to exit programming mode. > > No need for resistors at all. > > > > On Oct 14, 2017, at 8:38 PM, Eric Page wrote: > > > > > > Wade, > > > > Question: do you want to be able to adjust the scan rate as a matter of > routine operation (i.e. with a panel-mounted knob), or do you envision > setting the rate where you like it at installation, and leaving it alone? > > > > The answer will dictate whether we put a small trimmer potentiometer on > the circuit board or design for a larger panel-mounted potentiometer and > knob. > > > > Eric > > > Virus-free. www.avast.com <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> ________________________________ Message 3 _____________________________________ Time: 05:42:34 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter Yes, you do have to make it usable. But =9Cpush to advance, push-and-hold to cycle=9D is fairly str aightforward. (If that=99s too complex, do you really want to fly with this person?!) When it comes to changing the cycle period I=99m confident that a one- button interface can be very straightforward for that too. Certainly easier t han opening the panel to adjust a twiddle pot, or getting out a soldering ir on. A panel pot is simplest, but do you really want to drill your panel for a control you=99re going to set on day one and then forget about? So, it=99s not about tricks. It=99s about tucking away seldom us ed functions but still having them at your finger tips. On Oct 15, 2017, at 08:30, Charlie England wrote: That stuff is cool as far as programming tricks go, but who will be able to u se the hardware except the original designer? I, and everyone else on this l ist, have owned dozens of electronic gadgets over the years that are absolut ely impossible to set up and use without the English-as-a-second-language pr inted manual that you can't find after the 1st month of ownership. I have to use google on my desktop to explore how to get my phone apps to work like I want. Just something to consider, when designing for general use instead specifica lly trained fighter pilots or astronauts. > On Sat, Oct 14, 2017 at 11:43 PM, Alec Myers wrote: > > If you use a PIC, you could (trivially) do the following: > > Hold the button down for ten seconds to enter programming mode. Press the b utton briefly x times to set the scan period at x seconds. Press the button f or two seconds to exit programming mode. > > No need for resistors at all. > > > > On Oct 14, 2017, at 8:38 PM, Eric Page wrote: > > > > > > Wade, > > > > Question: do you want to be able to adjust the scan rate as a matter of r outine operation (i.e. with a panel-mounted knob), or do you envision settin g the rate where you like it at installation, and leaving it alone? > > > > The answer will dictate whether we put a small trimmer potentiometer on t he circuit board or design for a larger panel-mounted potentiometer and knob .. > > > > Eric > > Virus-free. www.avast.com ________________________________ Message 4 _____________________________________ Time: 08:23:37 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter At 07:30 AM 10/15/2017, you wrote: >That stuff is cool as far as programming tricks go, but who will be >able to use the hardware except the original designer? I, and >everyone else on this list, have owned dozens of electronic gadgets >over the years that are absolutely impossible to set up and use >without the English-as-a-second-language printed manual that you >can't find after the 1st month of ownership. I have to use google on >my desktop to explore how to get my phone apps to work like I want. This is amongst the simplest PIC applications we'll ever encounter . . . once the first installation has combed out the nits . . . it seems unlikely that there would be many if any software upgrades. Another consideration is flexibility. Suppose the prospective end user wants only two cameras . . . or three? Different software . . . or strapped selection on the ECB? Then there's a matter of packaging. One can easily spend more time putting a gizmo in a box and installing it than it took to build the gizmo. Certainly, packaging issues are a major component of a development project. A possibility for this project is to package in a D-sub housing. The enclosure is an off-the-shelf, inexpensive product that simply snaps onto the final assembly. An ECB can be soldered directly into the gap between rows of solder-cups on a dsub. Emacs! and dropped into a plastic housing that simply snaps together. A product housed in a 15 pin back shell has these dimensions. Emacs! This project can probably be fitted into a 25 pin back shell. I perceive no particular advantage in taking power and signals on/off the board on RCA jacks . . . shielded wires are just as easily dropped onto d-sub pins. RCA plugs are not the most installer friendly connectors. With the extra pins, the user could intall jumpers on the connector to select 2, 3 or 4 cameras. Other jumpers might select 3, 4 or 5 seconds per step . . . etc. Then there's consideration for the constellation of end users. How many would even be willing, much less able to successfully assemble the thing? Companies I've worked for have often been very protective of details for how their product was put together . . . worries about people wanting to build it themselves. I've observed that the $cost$ to built one-off exceeds the selling price from a manufacturer who is set up to build in volume while working wayyyyyyy down on the learning curve. It seems likely that the best way to bring this project into the marketplace is to have it productionized after the initial development work is completed. Even if supported by availability of bare ecbs and programmed chips, it doesn't seem like many of these things would be built. Bob . . . ________________________________ Message 5 _____________________________________ Time: 08:38:25 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter The AD8184 is $8. Here=99s a project using $0.50 bus switch chips: https://hackaday.com/2007/03/14/diy-av-switch/ For our purpose the PIC does its own demux - one output pin per camera. Benefits: -2,3,5, however-many cameras, all equally simple. - You don=99t need to sequence cameras in order or equally, thus you c an have forward, left wing, forward, right wing as the sequence. Thoughts? On Oct 15, 2017, at 11:22, Robert L. Nuckolls, III wrote: At 07:30 AM 10/15/2017, you wrote: > That stuff is cool as far as programming tricks go, but who will be able t o use the hardware except the original designer? I, and everyone else on thi s list, have owned dozens of electronic gadgets over the years that are abso lutely impossible to set up and use without the English-as-a-second-language printed manual that you can't find after the 1st month of ownership. I have to use google on my desktop to explore how to get my phone apps to work lik e I want. This is amongst the simplest PIC applications we'll ever encounter . . . once the first installation has combed out the nits . . . it seems unlikely that there would be many if any software upgrades. Another consideration is flexibility. Suppose the prospective end user wants only two cameras . . . or three? Different software . . . or strapped selection on the ECB? Then there's a matter of packaging. One can easily spend more time putting a gizmo in a box and installing it than it took to build the gizmo. Certainly, packaging issues are a major component of a development project. A possibility for this project is to package in a D-sub housing. The enclosure is an off-the-shelf, inexpensive product that simply snaps onto the final assembly. An ECB can be soldered directly into the gap between rows of solder-cups on a dsub. and dropped into a plastic housing that simply snaps together. A product housed in a 15 pin back shell has these dimensions. This project can probably be fitted into a 25 pin back shell. I perceive no particular advantage in taking power and signals on/off the board on RCA jacks . . . shielded wires are just as easily dropped onto d-sub pins. RCA plugs are not the most installer friendly connectors. With the extra pins, the user could intall jumpers on the connector to select 2, 3 or 4 cameras. Other jumpers might select 3, 4 or 5 seconds per step . . . etc. Then there's consideration for the constellation of end users. How many would even be willing, much less able to successfully assemble the thing? Companies I've worked for have often been very protective of details for how their product was put together . . . worries about people wanting to build it themselves. I've observed that the $cost$ to built one-off exceeds the selling price from a manufacturer who is set up to build in volume while working wayyyyyyy down on the learning curve. It seems likely that the best way to bring this project into the marketplace is to have it productionized after the initial development work is completed. Even if supported by availability of bare ecbs and programmed chips, it doesn't seem like many of these things would be built. Bob . . . ________________________________ Message 6 _____________________________________ Time: 08:51:49 AM PST US From: Charlie England Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter Bob, My comment was about 'buttonology'; not building. I've got a little clock that's RF linked to Federal time broadcasts. It's totally impossible to use any of the elaborate built-in functions with out the manual, because it has two or three unmarked buttons, and to access the various functions, you need to know the "combination". No one can use the thing without the book in front of them. Same thing for most kilo-function watches, etc. Even my old Icom A-4 handheld comm is like that. I seldom use it, so even though I've owned it for over 20 years, I still don't know how to program frequencies into it. If it had a keypad, anyone could pick it up and enter '122.75', or '125.25', etc. But since it doesn't, the unwashed can only hold the up or down button until they see the freq they want. For me, a perfect example of something simplified to the point of un-usability. Charlie Virus-free. www.avast.com <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Sun, Oct 15, 2017 at 10:22 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 07:30 AM 10/15/2017, you wrote: > > That stuff is cool as far as programming tricks go, but who will be able > to use the hardware except the original designer? I, and everyone else on > this list, have owned dozens of electronic gadgets over the years that are > absolutely impossible to set up and use without the > English-as-a-second-language printed manual that you can't find after the > 1st month of ownership. I have to use google on my desktop to explore how > to get my phone apps to work like I want. > > > This is amongst the simplest PIC applications we'll > ever encounter . . . once the first installation > has combed out the nits . . . it seems unlikely > that there would be many if any software upgrades. > > Another consideration is flexibility. Suppose the > prospective end user wants only two cameras . . . or > three? Different software . . . or strapped selection > on the ECB? > > Then there's a matter of packaging. One can easily > spend more time putting a gizmo in a box and installing > it than it took to build the gizmo. Certainly, packaging > issues are a major component of a development project. > > A possibility for this project is to package in a > D-sub housing. The enclosure is an off-the-shelf, inexpensive > product that simply snaps onto the final assembly. > An ECB can be soldered directly into the gap between > rows of solder-cups on a dsub. > > [image: Emacs!] > > and dropped into a plastic housing that simply > snaps together. A product housed in a 15 pin > back shell has these dimensions. > > [image: Emacs!] > > This project can probably be fitted into a > 25 pin back shell. I perceive no particular > advantage in taking power and signals on/off > the board on RCA jacks . . . shielded > wires are just as easily dropped onto d-sub > pins. RCA plugs are not the most installer > friendly connectors. > > With the extra pins, the user could intall > jumpers on the connector to select 2, 3 or 4 > cameras. Other jumpers might select 3, 4 or > 5 seconds per step . . . etc. > > Then there's consideration for the constellation > of end users. How many would even be willing, > much less able to successfully assemble the > thing? Companies I've worked for have often > been very protective of details for how their > product was put together . . . worries about > people wanting to build it themselves. I've > observed that the $cost$ to built one-off > exceeds the selling price from a manufacturer > who is set up to build in volume while working > wayyyyyyy down on the learning curve. > > It seems likely that the best way to bring > this project into the marketplace is to have > it productionized after the initial development > work is completed. > > Even if supported by availability of bare > ecbs and programmed chips, it doesn't seem > like many of these things would be built. > > Bob . . . > ________________________________ Message 7 _____________________________________ Time: 09:12:52 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter It=99s an open offer to the group (I would enjoy contributing something) - if you=99d like some PIC code along the lines I suggested - one or maybe two buttons, with or without a rotary encoder (that would be my favourite solution) I can have it done by the end of the week, if Paul doesn=99t want to. That=99s a 1990=99s technology solution. If the group is more comfortable with a 555 and discrete components (a creditable 70=99s technology solution) then there=99s no need for software. The choice of interface - number of buttons or switches, panel mount speed control etc. really is down to the person who=99s going to be installing it, we should let them pick what they want. > On Oct 15, 2017, at 11:50 AM, Charlie England wrote: > > Bob, > > My comment was about 'buttonology'; not building. I've got a little clock that's RF linked to Federal time broadcasts. It's totally impossible to use any of the elaborate built-in functions with out the manual, because it has two or three unmarked buttons, and to access the various functions, you need to know the "combination". No one can use the thing without the book in front of them. Same thing for most kilo-function watches, etc. Even my old Icom A-4 handheld comm is like that. I seldom use it, so even though I've owned it for over 20 years, I still don't know how to program frequencies into it. If it had a keypad, anyone could pick it up and enter '122.75', or '125.25', etc. But since it doesn't, the unwashed can only hold the up or down button until they see the freq they want. For me, a perfect example of something simplified to the point of un-usability. > > Charlie > > Virus-free. www.avast.com > > On Sun, Oct 15, 2017 at 10:22 AM, Robert L. Nuckolls, III > wrote: > At 07:30 AM 10/15/2017, you wrote: >> That stuff is cool as far as programming tricks go, but who will be able to use the hardware except the original designer? I, and everyone else on this list, have owned dozens of electronic gadgets over the years that are absolutely impossible to set up and use without the English-as-a-second-language printed manual that you can't find after the 1st month of ownership. I have to use google on my desktop to explore how to get my phone apps to work like I want. > > This is amongst the simplest PIC applications we'll > ever encounter . . . once the first installation > has combed out the nits . . . it seems unlikely > that there would be many if any software upgrades. > > Another consideration is flexibility. Suppose the > prospective end user wants only two cameras . . . or > three? Different software . . . or strapped selection > on the ECB? > > Then there's a matter of packaging. One can easily > spend more time putting a gizmo in a box and installing > it than it took to build the gizmo. Certainly, packaging > issues are a major component of a development project. > > A possibility for this project is to package in a > D-sub housing. The enclosure is an off-the-shelf, inexpensive > product that simply snaps onto the final assembly. > An ECB can be soldered directly into the gap between > rows of solder-cups on a dsub. > > > > and dropped into a plastic housing that simply > snaps together. A product housed in a 15 pin > back shell has these dimensions. > > > > This project can probably be fitted into a > 25 pin back shell. I perceive no particular > advantage in taking power and signals on/off > the board on RCA jacks . . . shielded > wires are just as easily dropped onto d-sub > pins. RCA plugs are not the most installer > friendly connectors. > > With the extra pins, the user could intall > jumpers on the connector to select 2, 3 or 4 > cameras. Other jumpers might select 3, 4 or > 5 seconds per step . . . etc. > > Then there's consideration for the constellation > of end users. How many would even be willing, > much less able to successfully assemble the > thing? Companies I've worked for have often > been very protective of details for how their > product was put together . . . worries about > people wanting to build it themselves. I've > observed that the $cost$ to built one-off > exceeds the selling price from a manufacturer > who is set up to build in volume while working > wayyyyyyy down on the learning curve. > > It seems likely that the best way to bring > this project into the marketplace is to have > it productionized after the initial development > work is completed. > > Even if supported by availability of bare > ecbs and programmed chips, it doesn't seem > like many of these things would be built. > > Bob . . . > > ________________________________ Message 8 _____________________________________ Time: 10:28:28 AM PST US From: Bill Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter Ditto Charlie! do not archive On Sun, Oct 15, 2017 at 8:50 AM, Charlie England wrote: > Bob, > > My comment was about 'buttonology'; not building. I've got a little clock > that's RF linked to Federal time broadcasts. It's totally impossible to > use any of the elaborate built-in functions with out the manual, because it > has two or three unmarked buttons, and to access the various functions, you > need to know the "combination". No one can use the thing without the book > in front of them. Same thing for most kilo-function watches, etc. Even my > old Icom A-4 handheld comm is like that. I seldom use it, so even though > I've owned it for over 20 years, I still don't know how to program > frequencies into it. If it had a keypad, anyone could pick it up and enter > '122.75', or '125.25', etc. But since it doesn't, the unwashed can only > hold the up or down button until they see the freq they want. For me, a > perfect example of something simplified to the point of un-usability. > > Charlie > > > Virus-free. > www.avast.com > > <#m_3036080108603840177_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> > > On Sun, Oct 15, 2017 at 10:22 AM, Robert L. Nuckolls, III < > nuckolls.bob@aeroelectric.com> wrote: > >> At 07:30 AM 10/15/2017, you wrote: >> >> That stuff is cool as far as programming tricks go, but who will be able >> to use the hardware except the original designer? I, and everyone else on >> this list, have owned dozens of electronic gadgets over the years that are >> absolutely impossible to set up and use without the >> English-as-a-second-language printed manual that you can't find after the >> 1st month of ownership. I have to use google on my desktop to explore how >> to get my phone apps to work like I want. >> >> >> This is amongst the simplest PIC applications we'll >> ever encounter . . . once the first installation >> has combed out the nits . . . it seems unlikely >> that there would be many if any software upgrades. >> >> Another consideration is flexibility. Suppose the >> prospective end user wants only two cameras . . . or >> three? Different software . . . or strapped selection >> on the ECB? >> >> Then there's a matter of packaging. One can easily >> spend more time putting a gizmo in a box and installing >> it than it took to build the gizmo. Certainly, packaging >> issues are a major component of a development project. >> >> A possibility for this project is to package in a >> D-sub housing. The enclosure is an off-the-shelf, inexpensive >> product that simply snaps onto the final assembly. >> An ECB can be soldered directly into the gap between >> rows of solder-cups on a dsub. >> >> [image: Emacs!] >> >> and dropped into a plastic housing that simply >> snaps together. A product housed in a 15 pin >> back shell has these dimensions. >> >> [image: Emacs!] >> >> This project can probably be fitted into a >> 25 pin back shell. I perceive no particular >> advantage in taking power and signals on/off >> the board on RCA jacks . . . shielded >> wires are just as easily dropped onto d-sub >> pins. RCA plugs are not the most installer >> friendly connectors. >> >> With the extra pins, the user could intall >> jumpers on the connector to select 2, 3 or 4 >> cameras. Other jumpers might select 3, 4 or >> 5 seconds per step . . . etc. >> >> Then there's consideration for the constellation >> of end users. How many would even be willing, >> much less able to successfully assemble the >> thing? Companies I've worked for have often >> been very protective of details for how their >> product was put together . . . worries about >> people wanting to build it themselves. I've >> observed that the $cost$ to built one-off >> exceeds the selling price from a manufacturer >> who is set up to build in volume while working >> wayyyyyyy down on the learning curve. >> >> It seems likely that the best way to bring >> this project into the marketplace is to have >> it productionized after the initial development >> work is completed. >> >> Even if supported by availability of bare >> ecbs and programmed chips, it doesn't seem >> like many of these things would be built. >> >> Bob . . . >> > > ________________________________ Message 9 _____________________________________ Time: 12:19:47 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter At 12:26 PM 10/15/2017, you wrote: >Ditto Charlie! > >do not archive > >On Sun, Oct 15, 2017 at 8:50 AM, Charlie England ><ceengland7@gmail.com> wrote: >Bob, > >My comment was about 'buttonology'; not >building. I've got a little clock that's RF >linked=C2 to Federal time broadcasts. It's >totally impossible to use any of the elaborate >built-in functions with out the manual, because >it has two or three unmarked buttons, and to >access the various functions, you need to know >the "combination". No one can use the thing >without the book in front of them. Same thing >for most kilo-function watches, etc. Even my old >Icom A-4 handheld comm is like that. I seldom >use it, so even though I've owned it for over 20 >years, I still don't know how to program >frequencies into it. If it had a keypad, anyone >could pick it up and enter '122.75', or >'125.25', etc. But since it doesn't, the >unwashed can only hold the up or down button >until they see the freq they want. For me, a >perfect example of something simplified to the point of un-usability. Understand. The task before us doesn't present much of either programming or a control task. The trade offs between a two-position, spring-loaded switch and a single push-button are valid options where a the cadence of button ops will transition between scan and select modes. I sympathize with your frustration on the radio. I've been purchasing some VERY capable but cumbersomely programmed UHF transceivers and setting them up for our EMS crews to monitor the local hospital repeater. These radios will do lots of cool stuff but you need to learn how to do a hat-dance on the controls which consist of 6 push-buttons and a knob. Fortunately, I'm only setting them up for one frequency and then locking the controls. They can be programmed via serial cable and a utility that runs under Windows . . . I may explore that feature in due course. But in the mean time, the hat-dance tune for one frequency is simple and short. Bob . . . ________________________________ Message 10 ____________________________________ Time: 12:34:04 PM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter One of the difficulties of a project like this is that there=99s no clear design priority for those who=99d like to contribute. I=99ve designed and built a *lot* of hobby PIC projects (the first in 1996, I think) and sold a few too. I=99ve always tried to reduce the BoM to a minimum (compatible with the task) which means: - wringing absolutely the most out of a low functionality PIC with good code - minimizing connectors and controls - always way less reliable and more expensive than any other part both in money and time As the saying goes, an engineer is someone who can make for a penny what any fool can make for a pound. But that may not be the right priority here. Perhaps ease of construction, wider sense of =9Cownership=9D, adjustability-with-a-hot-soldering-iron are all more important. > On Oct 15, 2017, at 3:19 PM, Robert L. Nuckolls, III wrote: > > At 12:26 PM 10/15/2017, you wrote: >> Ditto Charlie! >> >> do not archive >> >> On Sun, Oct 15, 2017 at 8:50 AM, Charlie England > wrote: >> Bob, >> >> My comment was about 'buttonology'; not building. I've got a little clock that's RF linked=C3=82 to Federal time broadcasts. It's totally impossible to use any of the elaborate built-in functions with out the manual, because it has two or three unmarked buttons, and to access the various functions, you need to know the "combination". No one can use the thing without the book in front of them. Same thing for most kilo-function watches, etc. Even my old Icom A-4 handheld comm is like that. I seldom use it, so even though I've owned it for over 20 years, I still don't know how to program frequencies into it. If it had a keypad, anyone could pick it up and enter '122.75', or '125.25', etc. But since it doesn't, the unwashed can only hold the up or down button until they see the freq they want. For me, a perfect example of something simplified to the point of un-usability. > > Understand. The task before us doesn't > present much of either programming or > a control task. The trade offs between > a two-position, spring-loaded switch > and a single push-button are valid > options where a the cadence of button > ops will transition between scan and > select modes. > > I sympathize with your frustration on > the radio. I've been purchasing some VERY > capable but cumbersomely programmed UHF > transceivers and setting them up for our EMS crews > to monitor the local hospital repeater. > > These radios will do lots of cool stuff > but you need to learn how to do a hat-dance > on the controls which consist of 6 push-buttons > and a knob. Fortunately, I'm only setting > them up for one frequency and then locking > the controls. They can be programmed via > serial cable and a utility that runs under > Windows . . . I may explore that feature > in due course. But in the mean time, the > hat-dance tune for one frequency is simple > and short. > > > Bob . . . > ________________________________ Message 11 ____________________________________ Time: 01:06:30 PM PST US Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter From: "Paul A. Fisher" Eric, This project was your suggestion, so I'll bow to whatever you want to do. PIC, no PIC, one switch, two switches - whatever you like! I don't believe I have a need for this device, so my opinion on the user interface is irrelevant. Just for my own "education and recreation", I wrote and tested the PIC software I described (for a single on-on-(on) switch). It's very simple, but does what I think you asked. You are welcome to the code if you are interested. Alec seems to have a lot more experience that I do, so since he volunteered, we should let him contribute if you want to go the PIC route. Either way, it was a fun Sunday afternoon project... especially since the weather isn't that conducive to flying! Please let me know if I can be of service. Otherwise, I'll go back into lurker mode. Paul Fisher On 10/14/2017 7:32 PM, Eric Page wrote: > > > nuckolls.bob(at)aeroelect wrote: >> I propose we make this another open source program like the wig-wag was . . . I'll be pleased to set up a folder to host all the work product. > > Great. I kinda figured we were doing an open-source effort. With that in mind, I had a good think about this while slogging for six hours against 145-knot headwinds this morning... > > I think there are a few issues that argue against changing to a PIC microcontroller in this project. Wade alluded to the first one in his post this morning (which, along with one other from Clayton, has disappeared from the server) when he joked about the details being over his head: > > - It would make the project considerably less accessible to many builders. Anyone without a hardware programmer and the Microchip IDE software will either have to get them, then find the code to download and learn how to program the PIC, or buy a PIC with the code already loaded. On the other hand, anyone pretty much anywhere with a soldering iron and minimal skill can put my design together for as long as its jellybean components are available. > > - Software updates will require removing the unit from service, removing the PIC to send for reprogramming, or buying a new PIC to replace it. > > - A PIC won't simplify the user interface. We still need a switch for the run/hold/step function and a knob to adjust scan rate. Perhaps a system using buttons or a rotary encoder could be devised, but it would probably be less intuitive than the switch and knob. > > - If a PIC could replace the $7 video multiplexer chip, you could make a good case for lowering cost, but we're talking about replacing a couple of 50 to 80-cent jellybeans and a few passives that are tens of cents each -- about $3 total. Can anyone deliver a programmed PIC for $3 and make it worth their trouble? > > - The size of the PCB is going to be driven largely by the five RCA jacks, so deleting a 16-DIP and a few passives probably won't shrink the board appreciably. > > I think this is a case where a microcontroller may be overkill, given that suitable cheap ICs are readily available. Given the simplicity of the problem, wouldn't it make more sense to keep the solution simple? > > Thoughts? > > Eric > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=473555#473555 > > ________________________________ Message 12 ____________________________________ Time: 08:01:47 PM PST US Subject: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter From: "Eric Page" Well, I drafted a detailed response to all the discussion over the last day or so, when Windows 10 decided -- without any warning -- to reboot for a security update. No opportunity to save work, just a sudden blank screen. Absolutely INFURIATING, and not the first time it's happened. Anyway, I'll probably miss something, but here's what I covered, as best I can remember... 1. Alec mentioned the possibility of video glitches or rolling when the feed is switched from camera to camera, due to the lack of video sync or frame buffering. If this happens, I will have zero idea how to fix it. I'm what you might call an ambitious hobbyist, not an engineer. Is this a high-risk thing? I have no experience here; I just found the mux IC and drew a schematic around it. 2. Alec also mentioned a Hackaday project to make an A/V switch box... https://hackaday.com/2007/03/14/diy-av-switch/ That's a neat idea, but I struggle to understand how a digital bus switch IC can handle an AC video signal when a proper video mux needs pos/neg rails to do it. It apparently worked, but I don't understand it and comments below the project suggest that it shouldn't have worked. Again, I'm not an engineer... 3. Some good discussion between Alec and Charlie WRT user interface: buttons, knobs, switches, etc. My $0.02 is this: if we stay with discrete ICs, the interface remains a single toggle switch, and either a trimmer or knob/pot for scan rate. If we use a PIC, I would advocate for a rotary encoder with a dead simple interface: pushing the encoder switch toggles between scan and hold; when in scan mode, each click of rotation increments/decrements the pause time on each camera by 1 sec; when in hold mode, each click of rotation selects the next/previous camera feed. No user programming, just immediate response to user input. It would be nice if the PIC could write the selected scan rate to non-volatile memory each time it's changed, and recall it on power-up. 4. The AD8184 datasheet... http://www.analog.com/media/en/technical-documentation/data-sheets/AD8184.pdf ...has a section on board layout (pg 7) that suggests a bunch of RF voodoo (striplines, microstrips, guard rings, termination resistors, etc.) related to preserving the part's 700MHz bandwidth. According to this Maxim application note... https://www.maximintegrated.com/en/app-notes/index.mvp/id/750 ...a standard definition NTSC video signal occupies 4.2MHz of bandwidth and requires 18MHz of bandwidth for 0.5dB flatness (whatever that means...). So, is any of the RF voodoo necessary, or will standard PCB traces and copper ground pours suffice? Short traces will be difficult with RCA jacks, but would be easier using a D-Sub (see below). 5. Bob made some suggestions: A. Use a 10-turn potentiometer. I have a 1-turn cermet trimmer in the BoM right now ($0.79), but it's easily changed to a 10 or 20-turn ($1.43), or to pads for a remote pot ($0.76) if desired. B. Design for a D-25 backshell. Good idea, but will the video signals suffer on a shielded wire -vs- an RCA cable? If not, let's do it. These NorComp parts are the only ones I can find whose datasheet includes inside dimensions... https://www.norcomp.net/rohspdfs/BackShells/InternalDimensions/ID-983Series.pdf ...and it doesn't look like I can fit everything into the space in a D-25 shell. The D-37 shell should have room to spare. Bob, if you have a deep D-25, could you give me the part number? C. Use excess pins in the D-Sub as selection jumpers for number of cameras, scan rate, etc. I presume this would require a PIC pin to read each jumper. Or perhaps you could use a resistor ladder across multiple D-Sub pins and read the ladder voltage with a single PIC pin to determine which jumper is installed. Very good idea for setting number of camera inputs, but I don't see the point for scan rate; a trimmer (or rotary encoder) seems fine. D. Use ExpressPCB. I haven't used them for at least 20 years. I don't like their "walled garden" model or their prices. Their closed software is the antithesis of "open source," and I'm never in a big enough hurry to justify the expense. My work will produce standard Gerber files that any board fab can use. Anyone can order 3 copies of the board from OSH Park... http://www.oshpark.com/ ...for $5/sq inch with free shipping, or upload to any of a half dozen Chinese fabs... http://www.pcbshopper.com/ ...to get 10 copies of the board in 2-3 weeks for Read this topic online here: http://forums.matronics.com/viewtopic.php?p=473595#473595 ________________________________ Message 13 ____________________________________ Time: 08:07:56 PM PST US Subject: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter From: "Eric Page" Wade, We haven't heard from you for awhile. Since you're likely to be the guinea pig on this project, there are a few items you should have input on: - Do you have a preference WRT discrete ICs -vs- a PIC microcontroller? - Do you have any desires for additional features or functions that would push us in one direction or the other? - Of the user interface options you've seen discussed, what would be your preference? - For camera scan rate, would you prefer to set it once and forget it, or have an accessible control for routine use? - Would you prefer to install a device with five RCA jacks for signal and a 2-position header for power, or one D-Sub connector for everything? Clayton, you expressed interest in getting one of these also; feel free to offer your opinion on these questions too. Eric Read this topic online here: http://forums.matronics.com/viewtopic.php?p=473596#473596 ________________________________ Message 14 ____________________________________ Time: 08:44:41 PM PST US From: Alec Myers Subject: Re: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter I think the video sync problem could be a big deal. I would absolutely order a couple of cameras and the screen I intended to use and try switching between the sources with a mechanical toggle switch to get some confidence the result is going to be acceptable. A CD4066 advertises itself as a quad gate analog switch, and its only $0.60. Alternatively since nobody here (I presume) is an experienced analog video design engineer, maybe the $8 part is worth it for ease of implementation. Ive never seen a rotary encoder with a push-button functionality as well. Could we compromise on a single (on)-off-(on) toggle switch mounted left-right. Click left or right to go to next or previous camera; Hold left or right for a second or two to resume scan; Hold left or right for ten seconds to enter/exit speed change mode. The PIC programmer in me wants to run and hide from resistor ladder networks for setting parameters: A 16 pin PIC should have lots of spare pins for jumpers. If you dont want a speed programming mode there would even be enough pins left for a speed selector. > On Oct 15, 2017, at 11:01 PM, Eric Page wrote: > > > Well, I drafted a detailed response to all the discussion over the last day or so, when Windows 10 decided -- without any warning -- to reboot for a security update. No opportunity to save work, just a sudden blank screen. Absolutely INFURIATING, and not the first time it's happened. > > Anyway, I'll probably miss something, but here's what I covered, as best I can remember... > > > 1. Alec mentioned the possibility of video glitches or rolling when the feed is switched from camera to camera, due to the lack of video sync or frame buffering. If this happens, I will have zero idea how to fix it. I'm what you might call an ambitious hobbyist, not an engineer. Is this a high-risk thing? I have no experience here; I just found the mux IC and drew a schematic around it. > > > 2. Alec also mentioned a Hackaday project to make an A/V switch box... > > https://hackaday.com/2007/03/14/diy-av-switch/ > > That's a neat idea, but I struggle to understand how a digital bus switch IC can handle an AC video signal when a proper video mux needs pos/neg rails to do it. It apparently worked, but I don't understand it and comments below the project suggest that it shouldn't have worked. Again, I'm not an engineer... > > > 3. Some good discussion between Alec and Charlie WRT user interface: buttons, knobs, switches, etc. My $0.02 is this: if we stay with discrete ICs, the interface remains a single toggle switch, and either a trimmer or knob/pot for scan rate. If we use a PIC, I would advocate for a rotary encoder with a dead simple interface: pushing the encoder switch toggles between scan and hold; when in scan mode, each click of rotation increments/decrements the pause time on each camera by 1 sec; when in hold mode, each click of rotation selects the next/previous camera feed. No user programming, just immediate response to user input. It would be nice if the PIC could write the selected scan rate to non-volatile memory each time it's changed, and recall it on power-up. > > > 4. The AD8184 datasheet... > > http://www.analog.com/media/en/technical-documentation/data-sheets/AD8184.pdf > > ...has a section on board layout (pg 7) that suggests a bunch of RF voodoo (striplines, microstrips, guard rings, termination resistors, etc.) related to preserving the part's 700MHz bandwidth. According to this Maxim application note... > > https://www.maximintegrated.com/en/app-notes/index.mvp/id/750 > > ...a standard definition NTSC video signal occupies 4.2MHz of bandwidth and requires 18MHz of bandwidth for 0.5dB flatness (whatever that means...). So, is any of the RF voodoo necessary, or will standard PCB traces and copper ground pours suffice? Short traces will be difficult with RCA jacks, but would be easier using a D-Sub (see below). > > > 5. Bob made some suggestions: > > A. Use a 10-turn potentiometer. I have a 1-turn cermet trimmer in the BoM right now ($0.79), but it's easily changed to a 10 or 20-turn ($1.43), or to pads for a remote pot ($0.76) if desired. > > B. Design for a D-25 backshell. Good idea, but will the video signals suffer on a shielded wire -vs- an RCA cable? If not, let's do it. These NorComp parts are the only ones I can find whose datasheet includes inside dimensions... > > https://www.norcomp.net/rohspdfs/BackShells/InternalDimensions/ID-983Series.pdf > > ...and it doesn't look like I can fit everything into the space in a D-25 shell. The D-37 shell should have room to spare. Bob, if you have a deep D-25, could you give me the part number? > > C. Use excess pins in the D-Sub as selection jumpers for number of cameras, scan rate, etc. I presume this would require a PIC pin to read each jumper. Or perhaps you could use a resistor ladder across multiple D-Sub pins and read the ladder voltage with a single PIC pin to determine which jumper is installed. Very good idea for setting number of camera inputs, but I don't see the point for scan rate; a trimmer (or rotary encoder) seems fine. > > D. Use ExpressPCB. I haven't used them for at least 20 years. I don't like their "walled garden" model or their prices. Their closed software is the antithesis of "open source," and I'm never in a big enough hurry to justify the expense. My work will produce standard Gerber files that any board fab can use. Anyone can order 3 copies of the board from OSH Park... > > http://www.oshpark.com/ > > ...for $5/sq inch with free shipping, or upload to any of a half dozen Chinese fabs... > > http://www.pcbshopper.com/ > > ...to get 10 copies of the board in 2-3 weeks for > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=473595#473595 > > > > > > > > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.