Today's Message Index:
----------------------
1. 05:21 AM - Exhaust pipe removal (martinburns)
2. 10:38 AM - Re: Plain Vanilla re ....Ducati rectifier/regulators (Greg Fuchs)
3. 10:42 AM - 912 ULS SB New Fuel Pump (Richard Wheelwright)
4. 11:02 AM - Re: Re: Ducati rectifier/regulators (Greg Fuchs)
5. 11:36 AM - Re: Ducati rectifier/regulators ... a different perspective (Greg Fuchs)
6. 12:13 PM - Re: 912 ULS SB New Fuel Pump (Grahamhall123@gmail.com)
7. 12:19 PM - Re: Ducati rectifier/regulators ... a different perspective (Tony Renshaw)
8. 04:21 PM - Re: Ducati rectifier/regulators ... a different perspective (Fred Klein)
9. 09:13 PM - Re: Re: Ducati rectifier/regulators (Bud Yerly)
Message 1
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Subject: | Exhaust pipe removal |
We need to remove one of the front exhaust pipes from our Rotax 912UL to cure a
small leak at the ball joint. The exhaust is the XS mild steel one. The pipe
seems to be solid in the exhaust port.
Does anyone have a recommended way of loosening it?
--------
Martin Burns
G-OJHL
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=417460#417460
Message 2
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Subject: | Plain Vanilla re ....Ducati rectifier/regulators |
The best test of any solution IMHO is if it works and has history.
For the number of hours of usage being achieved 560, over 1000, etc...if
that is typical of an installation that supplys plenty of air to the
regulator, then that seems quite good.
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Kevin
Klinefelter
Sent: Wednesday, January 22, 2014 5:22 PM
Subject: Re: Europa-List: Plain Vanilla re ....Ducati rectifier/regulators
--> <klinefelter.kevin@gmail.com>
In the 914 installation: I mounted the Ducati in the intake plenum on the
passenger footwell. Should stay pretty cool in there! So far so good at 560
hours...
Kevin
> On Jan 22, 2014, at 2:37 AM, "Greg Fuchs " <gregoryf.flyboy@comcast.net>
wrote:
>
> --> <gregoryf.flyboy@comcast.net>
>
> I plan to use the Ducatti..possibly with helper diodes...but defer to
> those that have more time in the seat and have piped air to it...
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of Tony
> Renshaw
> Sent: Wednesday, January 22, 2014 1:37 AM
> To: <europa-list@matronics.com>
> Subject: Europa-List: Plain Vanilla re ....Ducati rectifier/regulators
>
> --> <tonyrenshaw268@gmail.com>
>
> Gidday,
> I have attempted to read this with interest as my project develops
> closer to the time when I might need to know this stuff, and it seems
> like some of you know an awful lot. So, does anyone have any wise sage
> solutions for a newbie, whether it is best to start with what I've
> already got, strapped to my boxed, zero timed 914, or whether since it
> is already way out of warranty, replace the rectifier now, and if so
> with what? I can justify buying another rectifier if it would help in
> my current stage, construction I.e. No need for dedicated cooling ducting,
or minimisation etc.
> thanks for any dumbed down ideas.
>
> Tony Renshaw
>
>
>
> Sent from my iPad
>
>
>
>
>
>
>
>
Message 3
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Subject: | 912 ULS SB New Fuel Pump |
912 uls Drivers
I have just fitted the new Rotax Fuel pump (912-063 (UL) R2 ) This pump is
of higher pressure than the old AC pump.
The Questions are:- Has anyone had any problems with the higher pressurizer
of the Rotax stated 5.8 psi and 7.2 psi MAX ?
Why do they give 2 high MAX pressures?
My pressure is indicating 5.8psi 2500 rpm and 5 psi at 5400 rpm static, this
seems to be the new "normal range" for my aircraft.
Richard
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=417489#417489
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Subject: | Re: Ducati rectifier/regulators |
Using an encapsulated bridge seems like a great plan, and can easily be
found at almost any electrical supplier.
They have Fast-on connectors, for easy integration with the Ducati (finally
got the spelling right). These parts also seem to have the right qualities:
GBPC35 series Bridge Rectifier from Fairchild or the GBPC35A from Vishay (be
sure not to get the 'w' version, which has wires instead of fast-ons). One
could go with higher amperage, but the price seems to exponentially increase
if going much higher, and these are only about $3.00 for the first and a few
more for the second. Besides, only 2 of the 4 diodes are to be used. If it
ever fails, the other two diodes can be accessed. It's like having a spare
part being carried around at all times, so according to Remi, I guess that
means the first two will never fail. ...Its a Murphy work-around :)#)
Of course, it would still be good to have a few more reports from people
that have breathed life back into their regulators, just to prove that the
diodes are a common failure. That could be done with a completely burned out
regulator, two 10-cent silicon diodes from Radio Shxxx(Spares?) and a small
load, such as a light bulb...
Greg, A050
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of h&jeuropa
Sent: Wednesday, January 22, 2014 4:59 AM
Subject: Europa-List: Re: Ducati rectifier/regulators
The problem with external diodes as mentioned above is that the heat sink
they mount to will be at battery voltage. A better solution is to use a
bridge rectifier so the diodes are insulated from the mounting package.
Then the heat sink will be electrically independent. Such a bridge is a
Vishay 36MB120A ($8). This is a 35 amp, 1200 volt device which is similar
to the original Ducatti diodes. I plan to install this Spring.
Jim Butcher
N241BW
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=417406#417406
Message 5
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Subject: | Ducati rectifier/regulators ... a different perspective |
Pete-
Is this approach noisy at all? Can you hear any high-pitched whine in
the
audio system? Any insight into the switching converter (such as the
power it
can handle, where it is available, cost, etc). Either way, this could
come
in handy too, possibly for backup of the Ducati during flight. After
all, in
the 914, the pumps need to keep spinning and the time electrical
problems
crop up always seems to be at the most in-opportune time, like between
land
masses :).
I will be giving up the pad which would have been for the second
alternator, in order to place the oil regulator for the constant-speed
prop.
The front alternator alternative would require cowl mods, so it might be
an
easy two-wire switch-in solution for at least or just the pump, if our
infamous regulator fails (and assuming open diodes and not shorted scr's
is
the normal failure mode).
Backup also requires a reliable stator. Has anyone ever had the charging
coils go out?
Regards,
Greg
_____
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Peter
Zutrauen
Sent: Tuesday, January 21, 2014 10:38 AM
Subject: Re: Europa-List: Ducati rectifier/regulators ... a different
perspective
Just as an aside......
Fwiw for my other homebuilt I added a custom tiny alternator (actually a
high-current model airplane 3-phase brushless permanent magnet
"outrunner"
motor) I decided to not fully load the alternator constantly with these
wasteful regulators (in an effort to save power as well as longevity)
but
instead let the rectified bus voltage climb to whatever the alternator
will
produce (~27V at cruise RPM). I then use a high-frequency switching
convertor (a potted single module) to convert down to 13.4V for
charging
the battery. The convertor comes on line at an input voltage > 17V.
Seems
to work well so far.
Cheers,
Pete
A239
On Tue, Jan 21, 2014 at 1:06 PM, nigel_graham@m-tecque.co.uk
<nigel_graham@m-tecque.co.uk> wrote:
I have followed this discussion with great interest and with an
increasing
sense of D=E9j=B1 vu.
When the issue of regulator/rectifier failures occur withing the Rotax
community, the standard fix seems to be to simply replace like with like
(at
elevated Rotax pricing) and fly on until the next unit fails.
Up until about five years ago, nearly all modern Japanese motorcycles
used
the same technology as that found on the Rotax 91x series engines,
permanent-magnet generators controlled by SCR rectifier/regulators. It
may
come as some surprise that for an industry renowned for precision and
reliability, nearly all of these major motorcycle manufactures have at
some
time, been plagued by problems with their SCR based rectifier/regulators
failing and burning out alternators and wiring, cooking batteries and in
extreme cases, squirting unregulated AC into the wiring loom and blowing
up
ECUs. It was just such a failure that "sparked" my interest :-(
Known as "Shunt Regulators" the SCR technology runs extremely hot and
requires more cooling air than modern styling and space allows.
The solution was a move towards MOSFET controlled regulators and the
numerous web-based one-make discussion groups were full of information
and
advice on the reasons for failure, the benefits of the change and
practical
advice on how to convert.
It was by trawling these groups that I was able to build up a good
understanding of how these R/Rs worked, what was causing the problem and
what the potential solution might be. I compiled what I considered to be
the
best informed snippets of information into the attached document.
The first half gives an overview of a typical design of an SCR
Rectifier/Regulator for use on a permanent-magnet generating system and
the
second half discussed the relative merrits of SCR versus MOSFET.
It would be interesting to know which technology the the after-market
Schicker and Silent-Hektic R/Rs use.
Nigel
Message 6
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Subject: | Re: 912 ULS SB New Fuel Pump |
Have you seen this month and last month's safety spot in light aviation magazine?
Bit of info on the new pump.
Best wishes,
Graham.
On Jan 23, 2014, at 6:41 PM, "Richard Wheelwright" <rpwheelwright@yahoo.co.uk>
wrote:
>
> 912 uls Drivers
>
> I have just fitted the new Rotax Fuel pump (912-063 (UL) R2 ) This pump is
of higher pressure than the old AC pump.
> The Questions are:- Has anyone had any problems with the higher pressurizer
of the Rotax stated 5.8 psi and 7.2 psi MAX ?
> Why do they give 2 high MAX pressures?
> My pressure is indicating 5.8psi 2500 rpm and 5 psi at 5400 rpm static, this
seems to be the new "normal range" for my aircraft.
>
> Richard
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=417489#417489
>
>
>
>
>
>
>
>
>
>
Message 7
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Subject: | Re: Ducati rectifier/regulators ... a different perspective |
Hi Paul,
Hope the jumping is going well, and the flying. You a bit cold over there? I
am in LA, having spent 4 days here going batty since my LAX-JFK-LAX legs we
re cancelled due to the weather and light passenger loads. So, boring. Can y
ou tell me with this rectifier topic, would you replace the original rectifi
er with a GR6 straight from the get go? When they fail, does your alternator
just fail to charge, or can it overcharge? Is that why you have that OPV? C
ircuit?
Any help to get to the bottom of this electrical stuff appreciated. My build
is going ok at the moment. I have wings on, and am doing Fred Kleins fairin
gs at the moment, the P51 ones. They look good but gee there is a lot of wor
k to connect them, nearly as much as building them from scratch I would thin
k. Anyway, 60% done. Have mated the aileron quick connect pivot bolts and bo
nded the tufnol pads on them, so now to insy
Tall them and see how I went. I'm confident it should be good because of the
bolt work. Painting the interior before top goes on. Easy, light, and simpl
y quick progress, plus easy to modify, touch up as time goes on. Top goes on
soon, with Kingsleys help. Then on its wheels and I then have to turn it ov
er somehow to do some gear fairing work. That will be a challenge. I am thin
king of making carbon floor inserts, that come out like a tray, and just was
h out. Easy to make. Would that be a good idea do you think?
On a work topic, I was talking about you to a GE person, and I realised I do
n't know what you do, so, can I ask?
Fly safe, jump safe.
TR
Sent from my iPad
> On 21 Jan 2014, at 5:07 pm, Paul McAllister <paul.the.aviator@gmail.com> w
rote:
>
> David,
>
> I am kinda, sorta with you on this. Mine failed the same way after 10 year
s, however I do have an OPV system that disconnects the alternator from the
system just in case.
>
> I installed a GR6 once my original regulator died and went to heaven and s
o far so good.
>
> Paul
>
>
>> On Tue, Jan 21, 2014 at 4:15 PM, David Joyce <davidjoyce@doctors.org.uk> w
rote:
uk>
>>
>> Tim, I absolutely accept that it is not ideal and could cause more seriou
s problems than simple lack of charge, but one benign failure in 12 years of
flying is pretty close to acceptable reliability for me, and I enjoy glidin
g anyway!
>> Happy Landings, David
>>
>>
>> On Tue, 21 Jan 2014 19:31:56 +0000
>> houlihan <houlihan@blueyonder.co.uk> wrote:
>>> Hi David.
>>>
>>> One thing to bear in mind is that there are, as I understand it, several
>>> modes of failure of the Ducatti unit the most benign being that it just
>>> stops charging the battery and feeding the services.
>>> This is as you describe and as I also suffered ( why does this happen mi
d
>>> channel?) but I believe it can fail and possibly allow high voltage DC o
r
>>> AC onto the bus giving your expensive radio and other clever stuff a rea
l
>>> hard time !
>>>
>>> In the UK there is very little difference in cost between the Schicke an
d
>>> the Ducatti they are very similar in size and the wiring is only slight
ly
>>> changed , one wire not connected, and the generator fail light has to
>>> become an LED.
>>>
>>> Tim
>>>
>>>
>>>
>>> On 21 January 2014 19:13, David Joyce <davidjoyce@doctors.org.uk> wrote:
>>>
>>>> davidjoyce@doctors.org.uk>
>>>>
>>>>
>>>> Nigel, Fascinating and impressively erudite. You have totally convinced
me
>>>> that the way all new builders should go is with a Mofset bit of kit.
>>>> However my personal solution is to take the odd Ducatti at sale price o
ff
>>>> anyone not planning to fit them and fly with a spare! In 1000hrs I have
had
>>>> one failure. That was inconveniently 1/3 way between Holland and Clacto
n,
>>>> but there was enough juice in the battery to get me all the way home wi
th a
>>>> bit of thoughtful systems management. I currently fly with Rowland's
>>>> spurned new Ducatti in my spares department under pax seat, but am prep
ared
>>>> to offer a modest price for another unwanted Ducatti!
>>>> Regards, David
>>>>
>>>> On Tue, 21 Jan 2014 18:06:24 +0000
>>>> "nigel_graham@m-tecque.co.uk" <nigel_graham@m-tecque.co.uk> wrote:
>>>>
>>>>>
>>>>> I have followed this discussion with great interest and with an
>>>>> increasing sense of D=C3=A9j=C3- vu.
>>>>> When the issue of regulator/rectifier failures occur withing the Rotax
>>>>> community, the standard fix seems to be to simply replace like with li
ke
>>>>> (at elevated Rotax pricing) and fly on until the next unit fails.
>>>>>
>>>>> Up until about five years ago, nearly all modern Japanese motorcycles
>>>>> used the same technology as that found on the Rotax 91x series engines
,
>>>>> permanent-magnet generators controlled by SCR rectifier/regulators. I
t may
>>>>> come as some surprise that for an industry renowned for precision and
>>>>> reliability, nearly all of these major motorcycle manufactures have at
some
>>>>> time, been plagued by problems with their SCR based rectifier/regulato
rs
>>>>> failing and burning out alternators and wiring, cooking batteries and i
n
>>>>> extreme cases, squirting unregulated AC into the wiring loom and blowi
ng up
>>>>> ECUs. It was just such a failure that "sparked" my interest :-(
>>>>>
>>>>> Known as "Shunt Regulators" the SCR technology runs extremely hot and
>>>>> requires more cooling air than modern styling and space allows.
>>>>> The solution was a move towards MOSFET controlled regulators and the
>>>>> numerous web-based one-make discussion groups were full of information
and
>>>>> advice on the reasons for failure, the benefits of the change and prac
tical
>>>>> advice on how to convert.
>>>>>
>>>>> It was by trawling these groups that I was able to build up a good
>>>>> understanding of how these R/Rs worked, what was causing the problem a
nd
>>>>> what the potential solution might be. I compiled what I considered to b
e
>>>>> the best informed snippets of information into the attached document.
>>>>> The first half gives an overview of a typical design of an SCR
>>>>> Rectifier/Regulator for use on a permanent-magnet generating system an
d the
>>>>> second half discussed the relative merrits of SCR versus MOSFET.
>>>>>
>>>>> It would be interesting to know which technology the the after-market
>>>>> Schicker and Silent-Hektic R/Rs use.
>>>>>
>>>>> Nigel
>>> ===========
>>> ===========
>>> ===========
>>> ===========
>>
>> =========================
>> target="_blank">http://www.matronics.com/Navigator?Europa-List
>> =========================
>> http://forums.matronics.com
>> =========================
>> le, List Admin.
>> ="_blank">http://www.matronics.com/contribution
>> =========================
>
>
>
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3
D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>
Message 8
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Subject: | Re: Ducati rectifier/regulators ... a different perspective |
On Jan 23, 2014, at 12:18 PM, Tony Renshaw wrote:
> have wings on, and am doing Fred Kleins fairings at the moment, the
P51 ones. They look good but gee there is a lot of work to connect them,
nearly as much as building them from scratch I would think.
...in your dreams Tony...
:-))
Fred
Message 9
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Subject: | Re: Ducati rectifier/regulators |
=0A
=0A
=0A
Jan=2C and others=2C
Thanks for cleaning up my jargin. In my feeble mind the thyrister disconne
ct is just dumping the power from the output. Your explanation shows true
knowledge of these components. Whether it dumps or shorts or snorts=2C I
agree that the problem is not worth repairing. One could try to fix the Du
cati=2C but as you say=2C if its broke=2C it is best to just replace it...
Great idea from Kevin on putting the regulator on the 914 duct=2C or Remi
's idea on an aluminum plate to absorb more heat. However=2C what is the tr
ack record on the others using the GR6 or SH. Without testing on a plane w
ith known current draw=2C specifics on the RPM variations=2C battery condit
ion etc. what is good for one may not work for all. I know Paul has a fair
ly high draw aircraft (probably close to 15 amps)=2C and some extra data wo
uld be nice... However=2C I would like to see all of us not throw good mo
ney after bad or waste our time. My plane just doesn't draw enough power t
o kill the Ducati so I must experiment on more electrically thirsty planes
and listen to the lessons of others.
I have now completed quite a number of aircraft=2C nearly all are running a
nd working well. From the electric side=2C it seems to me we should set a
basic guideline for what to do electrically from the bus supply side for ou
r new owners/builders. Lord knows I have made many compromises using every
thing from split busses to dual alternators to get enough power to run stuf
f. Every client/builder has his own desires on the type of equipment he wan
ts=2C but usually doesn't have a clue on what really happens when all the t
oys get turned on. The Rotax install manual gives one the impression the n
ew Rotax/Ducati combo is a 22 amp 14.2 volt system above 1000 + 250 RPM. I
haven't seen that output at 2000 RPM except before the avionics were turne
d on. (That data was upgraded from the old 13.6 above 2000RPM from my old r
egulator). We know the Rotax / Jabiru charging systems do not produce enoug
h power to charge=2C at low RPM as during taxi=2C pattern=2C and landing ro
ll out with all the stuff on. There is nothing worse than an electrical sy
stem that is depleted due to low RPM running with a slightly old battery=2C
and on final=2C when you key the mic=2C the radio shuts down and EFIS rebo
ots due to a low battery condition brought on by running only 30 minutes at
or below 4000 RPM. On landing roll out you have to shut down everything a
nd run the engine up to talk on the radio. My rule of thumb is "the Rotax
charging system can only produce 15 amps at 13 volts above 4000 RPM" (at 1
8 amps the voltage just begins to drop off a bit) and electrical power requ
irements must be reduced below 4000 RPM or you must have a battery of suffi
cient capacity to supply the deficiency of the charge system. I build a
power requirement sheet with each panel I build or supervise. That works g
reat at cruise=2C but doesn't give the full picture at low RPM/High current
draw phases of flight=2C so we hope the battery was fully charged well pri
or to pattern entry. If you are an amp zealot=2C but still want an aux fuel
pump=2C pitot heat=2C 100 watt landing light=2C strobes=2C heavy draw radi
o (Garmin 430 type)=2C Aux Radio=2C Mode S transponder continuously working
=2C autopilot=2C stereo high quality music system=2C external power plugs f
or our phones=2C I-pads and inflight video system=2C the Rotax charging sy
stem is not going to hack it. Perhaps in the situation above=2C it would be
prudent for a 914 builder (914 can draw 11 amps on its own with both pumps
running) to consider a belt driven alternator of 40 amps=2C and simply red
o the cowl front and keep the Rotax as a backup in case of belt failure. If
you build a 912S airplane with all LED lighting=2C Garmin 255 or Becker Co
m=2C Simple digital Transponder=2C Aux Boost=2C and maybe an autopilot for
cruise only and a paper map=2C then the Rotax / Ducati should be fine. The
GR6 or SH may be better and longer lasting to boot. In my opinion the Rot
ax system can't put out much more than 15 amps or so and as the current inc
reases=2C the voltage output starts to diminish (at least it does in my poo
r old airplane) . Just my thoughts.Bud
> Date: Mon=2C 20 Jan 2014 16:40:25 +0100
> From: jan_de_jong@casema.nl
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Re: Ducati rectifier/regulators
>
>
> Re two-phase bridge rectifier/regulator.
> The 2 thyristors in the rectifier bridge do not short the AC input or
> "dump" anything.
> On the contrary=2C they disconnect the DC output from the AC input when
> the output voltage threatens to exceed the set voltage.
> All output current passes through one branch of one diode and one
> thyristor in series half the time and through the other identical branch
> also half the time.
> Heat development is proportional to the output current and the voltage
> drop across a branch.
> Voltage drops increase somewhat with current=2C so heat development
> increases more than linearly with output current.
> In the Ducati device the diode is reportedly a MR2510 pill (typically
> 0.75V at 10A=2C 0.8V at 20A)=2C the thyristor can be a 2N6504 (typically
> 1.1V at 10A=2C 1.3V at 20A).
> So at 10A the two branches of the bridge are each expected to generate
> 0.5 x (7.5 + 11) = 9.25W (total 18.5W) of heat.
> And at 20A the two branches of the bridge are each expected to generate
> 0.5 x (16 + 26) = 21W (total 42W) of heat.
>
> (
> a failure mode for the Ducati device is reportedly the loss of
> continuity of a diode pill attachment through thermal cycling=3B fitting
> external parallel diodes has been proposed as a solution=3B replacing the
> whole device seems more sensible
> )
>
> Cheers=2C
> Jan de Jong
>
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>
>
>
=0A
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