---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 11/23/11: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 12:23 AM - Contributions Down By 20%... (Matt Dralle) 1. 07:25 AM - Re: Contributions Down By 20%... (Robert L. Nuckolls, III) 2. 01:11 PM - Re: PTT Y adapter for RST intercom (messydeer) 3. 08:54 PM - Re: Re: PTT Y adapter for RST intercom (Bob McCallum) 4. 09:39 PM - Re: PTT Y adapter for RST intercom (messydeer) ________________________________ Message 0 _____________________________________ Time: 12:23:37 AM PST US From: Matt Dralle Subject: AeroElectric-List: Contributions Down By 20%... Dear Listers, As of today, Contributions to the Matronics List Fund Raiser are lagging behind last year at this time by roughly 20%. I have a Fund Raiser each year simply to cover my operating costs for the Lists. I *do not* accept any advertising income to support the Lists and rely solely on the Contributions of members to keep the expenses paid. I run all of my own servers and they are housed here locally, and the Internet connection is a commercial-grade, T1 connection with public address space. I also maintain a full backup system that does nightly backups of all List-related data so that in the event of a server crash, all of the Lists and the many years of List archive data could be restored onto a new server in a matter of hours. All of this costs a fair amount of money, not to mention a significant amount of my personal time. I have a Fund Raiser each year to cover these costs and I ask that members that feel they receive a benefit from my investments make a modest Contribution each year to support the continued operation and upgrade of these services. If you enjoy the Lists, please make a Contribution today. I also offer some incentive gifts for larger Contribution levels. At the Contribution Web Site, you can use a credit card, Paypal, or personal check to show your support for the continuation of these services: http://www.matronics.com/contribution Or, drop a personal check in the mail to: Matt Dralle / Matronics 581 Jeannie Way Livermore CA 94550 Thank you for your support! Matt Dralle Matronics Email List Administrator ________________________________ Message 1 _____________________________________ Time: 07:25:48 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Contributions Down By 20%... At 02:20 AM 11/23/2011, you wrote: > > >Dear Listers, > >As of today, Contributions to the Matronics List Fund Raiser are lagging be >hind last year at this time by roughly 20%. Hey folks. It doesn't take much if everyone chips in . . . last time I looked, there were over 1800 subscribers to this list. For the price of a #2 at McD, 1800 folks could make a BIG difference in Matt's enthusiasm for keeping all the hardware running and the lights turned on. Bob . . . ________________________________ Message 2 _____________________________________ Time: 01:11:41 PM PST US Subject: AeroElectric-List: Re: PTT Y adapter for RST intercom From: "messydeer" I read this in the RST 442 documentation this morning: Some push-to-transmit switches are designed only for use with headsets and radios and leave the microphone audio line (this is the "ring" portion of the microphone plug) connected to the radio even when the radio is not transmitting. Since some radios ground (disable) the microphone audio in receive mode, this type of PTT switch is unsuitable for use with an intercom system. If you already have PTT switches in the aircraft you may wish to try them with your intercom. If, however, you find that you lose intercom function (microphones are weak, distorted, or dead) when you plug the "PILOT ICS" and "COPILOT ICS" plugs into the COM radio via these PTT switches you will need to either 1) change to a model switch which opens the audio line when not transmitting or 2) consult your local radio shop and have a relay installed to achieve the same effect. I found out my Dynon DX15 handheld radio sends power to the mic only when transmitting, so my last schematic wouldn't work. They suggested using DPDT switches for the PTT's. Unfortunately, the gatekeeper to the engineer I was corresponding with has cut me off, so I can't get any more answers from them. I drew what I hope will work for me. I would use 4 pieces of single conductor shielded wire with the braided shield carrying ground current. The intercom has extra ground wires coming out of it, so that's already set. An additional unshielded ground wire would go from the intercom to the shell of the plug to the handheld radio. How does this look? BTW, is it common for radios to operate this way? -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=359044#359044 Attachments: http://forums.matronics.com//files/rst_intercom_dpdt_ptt_with_shields_981.jpg ________________________________ Message 3 _____________________________________ Time: 08:54:36 PM PST US From: Bob McCallum Subject: RE: AeroElectric-List: Re: PTT Y adapter for RST intercom Not quite following you here. You've stated you're using DPDT switches for the PTT but you've depicted DPST in your sketch??? Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list- > server@matronics.com] On Behalf Of messydeer > Sent: Wednesday, November 23, 2011 4:08 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Re: PTT Y adapter for RST intercom > > > I read this in the RST 442 documentation this morning: > > Some push-to-transmit switches are designed only for use with headsets and radios > and leave the > microphone audio line (this is the "ring" portion of the microphone plug) connected to > the radio even > when the radio is not transmitting. Since some radios ground (disable) the > microphone audio in receive > mode, this type of PTT switch is unsuitable for use with an intercom system. If you > already have PTT > switches in the aircraft you may wish to try them with your intercom. If, however, you > find that you > lose intercom function (microphones are weak, distorted, or dead) when you plug the > "PILOT ICS" and > "COPILOT ICS" plugs into the COM radio via these PTT switches you will need to > either 1) change to a > model switch which opens the audio line when not transmitting or 2) consult your > local radio shop and > have a relay installed to achieve the same effect. > > I found out my Dynon DX15 handheld radio sends power to the mic only when > transmitting, so my last schematic wouldn't work. They suggested using DPDT > switches for the PTT's. Unfortunately, the gatekeeper to the engineer I was > corresponding with has cut me off, so I can't get any more answers from them. > > I drew what I hope will work for me. I would use 4 pieces of single conductor shielded > wire with the braided shield carrying ground current. The intercom has extra ground > wires coming out of it, so that's already set. An additional unshielded ground wire > would go from the intercom to the shell of the plug to the handheld radio. > > How does this look? > > BTW, is it common for radios to operate this way? > > -------- > Dan > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=359044#359044 > > > > > Attachments: > > http://forums.matronics.com//files/rst_intercom_dpdt_ptt_with_shields_981.jp g > > > > > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > > ________________________________ Message 4 _____________________________________ Time: 09:39:45 PM PST US Subject: AeroElectric-List: Re: PTT Y adapter for RST intercom From: "messydeer" Hmm...I didn't think if they were or weren't single or double throws. Here's Dynon's quote: "I took a look at your schematic and I don't think this configuration will work with the DX15..." He's referring to the earlier 'RST intercom mic out ptt wiring.jpg' diagram. ".. DX15 only sends power to the microphone while it is transmitting. Even if you were to use a DPDT, I'm not sure what effect having two microphones in parallel will have. It may cause the audio to become distorted if the DX15 cannot provide enough power for both microphones. The headset adapter we sell only has connections for one headset, so we have never tried that configuration. If you were to use two DPDT switches to make sure only one headset mic is connected to the DX15 at a time, I think that will give you the best results." Below is the drawing in the RST manual that helped me understand what Dynon was saying, so I copied the switch diagram the same. I've reviewed the difference between a DPDT and SPDT. Correct me if I'm wrong, but I thought a DPDT functions the same as a DPST when the correct 2 of the 6 contacts are left open. Semantics aside, would my drawing work? -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=359090#359090 Attachments: http://forums.matronics.com//files/rst_dptdt_or_dpst_switch_for_ptt_178.jpg ------------------------------------------------------------------------------------- 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.