[ARC5] ARC-5/R-25 tuning gang question

[WA5CAB at cs.com]

Jeep,

I haven't counted the plates in a long time but 10 sounds about right.  If 
you have the three volumes of Surplus Conversion Handbook, in one of the I 
think smaller ones there is an article on converting a Command Receiver 
(memory says a BC-454-B) to 10 Meters (which was all the rage in the late 
1940's).  I don't recall all of the details but a major part of the conversion was 
the removal of most of the plates from the tuning capacitor.  Ken has or had 
a receiver that had been so converted.  Everyone's first thought would 
probably be that such a conversion would work best with a BC-455 or R-27, and 
for image rejection they'd be right.  But as the conversion also included 
stripping and rewinding the front end coils and removing most of the tuning 
capacitor plates, the RF AMP, HFO and MIXER wouldn't care.  I wouldn't call the 
R-25 a good candidate but someone apparently did.

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480


In a message dated 01/30/2016 06:29:02 AM Central Standard Time, 
jeepp at comcast.net writes: 
> Hmmmm  I'm looking at one of the tuning caps and I count 10 plates?  Are 
> we talking about the same thing?
> 
> Jeep - K3HVG
> 
> On 1/29/2016 9:29 PM, J Mcvey via ARC5 wrote:
> 
> >> I just got into this decent R-25 specimen, which had been partially 
>> hacked under the chassis,. The Audio output transformer, 7K/10W, and the LV 
>> Choke had been removed and they have "cored out" the cable mount assembly 
>> to accommodate one of those "Ebay adaptor shafts". ( very unfortunate!) 
>> However It looks NOS, otherwise.
>>  One of the other things that was strange was that the 1st and 3rd IF 
>> cans were missing the mount screws and the hood over the gang cap was loose.
>>  
>> 
>> When I pulled the hood off, there were only three blades on each rotor 
>> shaft. Is this normal or was this a hack job?
>>  
>> 
>> I don't know if it works yet, because the RF stage is noisy/oscillating 
>> or something ( no antenna). The RF stage apears to be at least partially 
>> functional since I get a noise bump when I touch the antenna terminal. The 
>> noise goes away when I pull the grid cap. The other odd thing is that I 
>> don't hear much activity when I touch the open grid cap. 
>> 
>> It may just be bad caps...
>> 
>> 
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