[Milsurplus] BC-221-J

[Mike Hanz]

The TS-164 is actually an interesting exercise in minimally invasive 
engineering.  It uses the current detected by turning on the BC-221 
filament to turn on the B+ from the BC-348.  That way there was no need 
to change anything in the BC-221.  Sounds like the sort of philosophy 
most of us have adopted 60 years later to preserve these WWII sets!   
:-)   For those who are interested, I posted the original preliminary  
"manual" for the TS-164 at http://aafradio.org/docs/docs.html, under 
"Operational Notes."

73,
Mike

WA5CAB at cs.com wrote:

>Rick,
>
>What you have is a BC-221-J (hopefully the matched serial number calibration 
>book was also transferred - otherwise it isn't usable as a freq meter) that 
>was converted to TS-164/AR.  The original metal (in this case) cabinet with room 
>in the lower rear for dry batteries or Rectifier Power Supply RA-133-(*) was 
>discarded during the conversion.  
>
>The Jones plug is for a power cable that ran to PL-103 on the adjacent 
>BC-348, from which power was drawn (both A+ and B+).  There is a B+ voltage dropping 
>circuit and a filament voltage dropping resistor in the small compartment on 
>the rear of the CS-182/AR.  That may be what you see that lead you to say 
>someone had started building an AC supply.
>
>So the answer to both of your questions is "no".
>
>In a message dated 3/19/2006 11:46:13 AM Central Standard Time, 
>rickbras at airmail.net writes: 
>
>>I'm confused (like that's big news) about my BC-221-J.  Some one had 
>>started to build an AC supply for it or so it appears.  However, there 
>>is no room for a transformer in the back.  The specifics on this meter are:
>>
>>TS-164/AR
>>BC-221-J
>>CS-182/AR (metal case)
>>
>>If this used batteries they were very small for that era and flat.  
>>There is a 4 pin Jones type male socket on the right rear of the case as 
>>you're looking at the front.  It is original, I'm sure.  There's a 
>>harness going from this plug to the rear compartment.  There is a 
>>bathtub capacitor attached in the back compartment which seems to be 
>>original.  The harness runs through the metal divider between the front 
>>and rear compartments.
>>
>>Did this unit ever use batteries mounted inside the case or is the Jones 
>>connector there to connect an external battery pack or AC supply?  I 
>>have a couple of manuals (TM 11-300 and AN 08-40SCR211-2) but neither 
>>show pictures of this specific model.
>>
>>
>>
>
>Robert Downs - Houston
><http://www.wa5cab.com> (Web Store)
>MVPA 9480
><wa5cab at cs.com> (Primary email)
><wa5cab at houston.rr.com> (Backup email)
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