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THE AM BULLETIN BOARD => Military Amateur Radio Section => Topic started by: SM6OID on November 15, 2021, 12:44:32 PM



Title: Western Electric GF-11 Transmitter, seeking information!
Post by: SM6OID on November 15, 2021, 12:44:32 PM
Hello!

So, IF everything goes well, I will have a Western Electric GF-11 transmitter on the workbench in a not too distant future.
Anyone here with experience from using the GF-11?
I only have the transmitter, no junction boxes etc.
The GF-11 CW-52063A was used in Navy one and two seated aircraft, I believe, but more specific??

Words of wisdom... anyone?

Pictures to follow, of course.


Title: Re: Western Electric GF-11 Transmitter, seeking information!
Post by: KA3EKH on November 16, 2021, 10:00:53 AM
Man, thatís a primitive transmitter. think the design dates back to the early thirties although they were produced up until early WW2. Low power and questionable stability can see where it would be used for local point to point communications but that may be the one radio thatís less desirable to use on the HF bands then the later series of ARC-5 or Command sets.
You are going to need a RU TRF Receiver to go with it to get the full pre-war experience. At least the RU receivers were somewhat better being they went on to be paired with things like the high-powered GO series transmitters in things like the PBY Catalina and in some Navy applications with the ART-13 but the GF series never went on to be anything beyond a small low power local communications radio.
The interesting thing is that the GF/RU was also used in boats and ground vehicles like ambulances, maybe that why you can find them and the dynamotors that were set up for twelve volt operation?
Once VHF FM radios became available the day of the low power AM sets was thru.  By 43 or so the BC-1000 and other radios quickly replaced all that stuff in ground operations and SCR-511, ARC-1 and ARC-3 sets in aircraft.
Its antidotal but I have noticed that most of the GF/RU stuff I have seen was never placed into operation and wonder how much of that stuff was built in the lead up to WW2 but then never installed being newer and better technology quickly left that stuff behind?  Anything being used in the D Day operation and after would have the newer VHF aircraft sets or the FM sets for ground operation and all that GF/RU stuff built five years before was left behind?
Radio Boulevard has a lot of pictures of the radio and all its stuff:
https://www.radioblvd.com/RU16-GF11_Restoration.htm



Title: Re: Western Electric GF-11 Transmitter, seeking information!
Post by: SM6OID on December 17, 2021, 03:28:40 PM
Hi!
It's alive...
Power out on CW is 16 W-ish and on AM I see 4 W worth of carrier, peaking 100% modulation.
Feeding it with 400 V from a regulated PS.
Have had a number of QSO's on CW and Ĺ a QSO on AM, that means that QSB killed us quite quick...

So far QSO only on 80 m, drift and chirp is not to bad.


Title: Re: Western Electric GF-11 Transmitter, seeking information!
Post by: KC4VWU on January 10, 2022, 06:56:17 AM
Wow! Looks like new. The ones I have are pretty ratty looking. Seems you also have a good coil set:keep that locked up in the safe when not in use!


Title: Re: Western Electric GF-11 Transmitter, seeking information!
Post by: Opcom on January 12, 2022, 12:04:22 AM
Indeed a beautiful specimen and love the dynamotor in the background


Title: Re: Western Electric GF-11 Transmitter, seeking information!
Post by: SM6OID on January 12, 2022, 07:55:05 AM
Hi!
Update and answers...

First, I have made a number of both CW and AM QSO's by now.
On AM I use an old trusted T-17 mic, modulates well and readability is good!
So far only QSO's on 80 m, but I also have a coil set for 40 m.

I'm sure that I'm the first user of this transmitter.
No repairs, no modifications, no signs of ever being used.
The 40 m coil set is matching numbers, the 80 m is not.
However, PA grid leak resistor has drifted, so that one possibly should be replaced.

I run the transmitter from a stabilized 400 V supply, the dynamotor in the background is for one of the ART-13's.
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