[ARC5] WWII Aircraft Set- Primer?

[Mike Morrow]

Yes, George, the GO-6 is in my list of the 11 GO systems, and I mention you and your unique GO-6 HF transmitter in the text below the listing.

Mike / KK5F

-----Original Message-----
>From: George Babits <gbabits at custertel.net>
>Sent: May 7, 2018 7:22 PM
>To: Mike Morrow <kk5f at arrl.net>, arc5 at mailman.qth.net
>Subject: Re: [ARC5] WWII Aircraft Set- Primer?
>
>there was a GO-6 too.  I have one.
>
>George
>W7HDL
>
>----- Original Message ----- 
>From: "Mike Morrow" <kk5f at earthlink.net>
>To: <arc5 at mailman.qth.net>
>Sent: Monday, May 07, 2018 6:15 PM
>Subject: Re: [ARC5] WWII Aircraft Set- Primer?
>
>>> ...the aircraft version on the TBW was the GO-9...
>>
>> And the principal electrical distinction was the TBW's 843 PA grid 
>> modulator stage. which allowed A3 emission.  The GO-9 is A1 and A2 
>> only...with A2 generated from the 800 Hz primary AC power.
>>
>>> Question, somehow I have only ever seen GO-9, was there a GO-8 or 7?
>>
>> There were 11 different GO-series liaison transmitter systems between 1933 
>> and 1944. All were A1 and A2 emission.  The intermediate frequency 
>> transmitter for all covered 300 to 600 kHz MF.  The HF transmitter 
>> frequency coverage in kHz varied:
>>
>> GO      1933     Hygrade-Sylvania     4000-13575
>> GO-1    1934     Western Electric     3000-13575
>> GO-2    1935     Western Electric     3000-13575
>> GO-3    1937     Westinghouse         3000-13575
>> GO-4    1938     General Electric     3000-26500
>> GO-5    1939     General Electric     No HF unit
>> GO-6    1939     General Electric     3000-26500 (No IF unit)
>> GO-7    1940     Westinghouse         3000-13575
>> GO-8    1940     Westinghouse         3000-13575
>> GO-9    1940     Westinghouse         3000-18100
>> GO-9a   1944     Westinghouse         2200-18100
>>
>> The scant surviving technical information indicate that there were major 
>> design differences from one manufacturer to another.  Most except the GO-9 
>> were likely made in quantities well under 100, so very little equipment or 
>> tech info has survived for most GO sets..
>>
>> List member George has what is probably the only surviving 1939 GO-6 HF 
>> transmitter, and the Pensacola Naval Aviation Museum has a cutaway PBY on 
>> display that appears to have a 1935 GO-2.  Everything else that has 
>> survived seems to be a GO-9 unit.
>>
>>> Also the TBW and the GO-9 were so close but yet not the same,
>>> how did that happen?
>>
>> Patrol plane communication service requirements differ greatly from those 
>> of "portable" ground communications service.  What is remarkable is that 
>> the GO-9 and TBW transmitter units are so similar, not that they differ in 
>> small details.
>>
>>> What came first?
>>
>> The first GO was made in 1933, and the first Westinghouse GO-3 in 
>> 1937...years before the Westinhouse TBW.
>>
>> Some other GO-related notes:  I believe the amazing upper limit of 26500 
>> kHz for the 1938 GE GO-4 is what motivated A.R.C. to develop the RAT and 
>> RAT-1 (13500 to 27000 kHz) sets to extend liaison receiver coverage beyond 
>> the 13575 kHz limit of the RU-11 and RU-12 liaison receivers.  Further, it 
>> seems that A.R.C. designed the eight-receiver RAV 190 to 27000 kHz set to 
>> replace the RU-12/RAT-1 with modern superheterodyne receivers.  However, 
>> the A.R.C. RAV was definitely the inferior set in most qualities to GE's 
>> RAX-1 three-receiver liaison system.  The RAX-1 had much better staging in 
>> its two receivers that provided most of its 200 to 27000 kHz coverage. 
>> Only 46 RAV liaison receiver sets were made, while the RAX-1 was made in 
>> the thousands.
>>
>> A.R.C. made up for it with five receivers identical to or very slightly 
>> simplified from the RAV system becoming standard "command" set radios 
>> purchased by the tens of thousands.
>>
>> Mike / KK5F