IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

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CrazyFin
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IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by CrazyFin »

Hi

New on the forum and I have read through all the posts in the thread "Aeroflex (IFR) Questions".

I recently got hold of a nice IFR / Aeroflex and formerly Marconi 2945A comm test set.
It really works fine and for me being a pure hobbyist in electronics and radio comms this test set is a dream for me. I can now reduce some of my bigger and more heavy instruments from my home lab.

I have read through the user and service manual and I can't find any information if the option 8, SSB demodulator is possible to retrofit.

I read in @Wowbagger's post http://batboard.batlabs.com/viewtopic.p ... 5a#p469518 in the Aeroflex (IFR) Questions thread that
"Software upgrade and purchasing of options and manuals should be handled though Service, just like anything else - I know they can handle that line."
The above post was made in Nov 2013 by @Wowbagger and I see now that Aeroflex is a divison of Cobham nowadays. I have contacted Cobham several times asking to buy the option 8 but I have not yet got any reply back. It was 2-3 months ago now and still no reply.

@Wowbagger: Do you have any contact details for the specific service department that MIGHT be able to help me out purchasing the option 8 SSB demodulator for 2945A?
CrazyFin
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Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by CrazyFin »

Ok, I have now received an answer from Cobham, department "EMEA Service and Support":
Thank you for your email, unfortunately the 2945A is an end of service product and therefore on this occasion we cannot assist you.
My odds for finding the wanted SSB demodulator for my 2945A decreases quite much now... :cry:
I hope I can find someone who is selling a 2945A with option 8 as a parts unit for a fair value OR someone willing to sell their module option 8 outright.

Remaining question still exists if it is possible to retrofit this option 8 or does it require software programming of the 2945A as well?

I do have both the user manual AND service manual but I can't find any information about retrofitting modules into an existing instrument that has had the option NOT installed previously.

I can only find information on how the option 8 module works and its connections and power supply levels. Section A15, page 1-59 in the service manual.
CrazyFin
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Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by CrazyFin »

UPDATE:

I have been able to find out from the service manual that if one is REPLACING the SSB demod card then there is NO need for recalibration of the unit. It does not state however, what kind of calibration and software updates are needed to install the SSB demod card into a unit as a retrofit.

I found this text in the Service Manual on page 1-59:

"Board replacement
Replacing this board with a substitute board will not affect the calibration of the Service Monitor.
"

I also found on page 3-13 the full calibration routine for the SSB demod card and when reading through I should be able to perform it as described since I have all the necessary equipment needed for that. (All are not in calibration anymore but I am not looking for calibration certification of my unit.)

I have not been able to find out though that if there is some software updates needed to ENABLE the card when it has been installed.


I also found out that there is a retrofit option article number called "RTROPT08-2945A" or "RTROPT08/2945A" so it seems that it has indeed been possible to purchase this option 8 SSB demod as a retrofit option. I have found one firm offering this retrofit option but I am not sure that they actually can do it or if it is just an old and not updated webpage.


I´ll keep on looking for either a broken or working 2945A with the SSB card or if someone who has the card installed that would be interested in selling it (unless it requires some kind of software programming in order to enable it).
If I find a working 2945A with the SSB card for a decent price I will then sell my current one.

I really love this instrument and really would like to keep it if I can find get the SSB option.
flyinace09
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Joined: Fri Dec 02, 2005 7:34 pm
What radios do you own?: XTS/XTL5000, AS+, etc.

Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by flyinace09 »

Welcome to my life with the IFR. I have a 2947 which was the FAA/Navy version of essentially a 2948. IFR will SELL me the service manual for around $400+, but just looking at the 2945 manual tells me that I would be having some fun maintaining my own equipment. And unlike the HP 89xx series with its modules, the IFR is a jam-packed rats nest of components in various spots and accessing some means disconnecting RF lines which means you cannot easily change something, plug it in, and check your work.

That being said - if you can tell me a part number and the location of it on a 2945, I can see if any of the surplus 2947s I have access to 1) have the same part, and 2) it’s a part that isn’t failing self-diagnostics. That was the reason we abandoned trying to repair the 2947s for use... almost all of them had something wrong. Only two of us ended up with working units off the pallet.
CrazyFin
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Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by CrazyFin »

flyinace09 wrote:if you can tell me a part number and the location of it on a 2945, I can see if any of the surplus 2947s I have access to 1) have the same part, and 2) it’s a part that isn’t failing self-diagnostics.
The only part numbers I have been able to find for the SSB option is the following:
"RTROPT08-2945A" or "RTROPT08/2945A" and since I do not have access to an actual SSB option module I have no clue what the part number on the board itself is.

I solved it the easy way... I sold the IFR 2945 to a professional user who did not need the SSB (he was looking for the paging signalling option which my unit had) and I bought a fully loaded HP 8920A for the same amount of money.
flyinace09
Posts: 67
Joined: Fri Dec 02, 2005 7:34 pm
What radios do you own?: XTS/XTL5000, AS+, etc.

Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by flyinace09 »

Not a bad choice - I have a nearly identically loaded 2947 and 8920A and usually pull the HP out to use more often. Mostly because parts are more readily available and I am less afraid to thus damage it moving it around. Only downside to the HP is I haven't figured out how to do DPL encode for some repeaters I want to test when they're already in the environment.
jry
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Re: IFR / Aeroflex / Marconi 2945A comm test - trying to find a way to buy Option 8, SSB demodulator for retrofitting

Post by jry »

do not mean to hijack the thread but the DCS is under the signalling options .
not as easy to configure on the 892X series but it works.
I usually have to play around with the settings to get the decode going
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