[Milsurplus] SCR-245, BC-223 PE-125-AX Vibrator Supply

[David Stinson]

That's excellent info, Robert.
Thank you!

----- Original Message ----- 
From: <WA5CAB at cs.com>
To: <arc5 at ix.netcom.com>; <milsurplus at mailman.qth.net>
Sent: Sunday, April 06, 2014 7:06 PM
Subject: Re: [Milsurplus] SCR-245, BC-223 PE-125-AX Vibrator 
Supply


> Dave,
>
> Don't let the 10 watt quoted power output figure mislead you. 
> Remember
> that the thing normally operates into a 15' whip antenna at 
> frequencies as low
> as 2 MC.  Quite inefficient.  From the SCR-245-AX manual, total 
> HV current
> in Voice at 550 VDC (presumably 14.2 VDC input) is 185 mA. 
> That's 101.75
> watts total input from the vibrator or dynamotor supply.  The 
> PE-237 used with
> the BC-1306 and early AN/GRC-9 uses (depending upon Order #) 4 
> or 5 HV
> transformers and a single very large 5PDT vibrator.  Of course, 
> it also has to
> operate on 6 VDC (which doubles the primary current that the 
> vibrator has to
> switch compared to the PE-125-AX).
>
> The SCR-245-AX manual gives 23 ADC as the peak input current at 
> 14.2 VDC.
> Some of that is of course heater and relay current.  My 
> recommendation, if
> you try to operate with only half of the supply working, is NOT 
> to try to run
> it on 12-14 VDC.
>
> In a message dated 04/06/2014 13:17:40 PM Central Daylight 
> Time,
> arc5 at ix.netcom.com writes:
>> Does anyone have experience with the PE-125-AX
>> vibrator power supply for the BC-223 transmitter?
>> The thing has two identical vibrator supplies
>> which are connected in parallel on the B+ output.
>> They have some heavy iron in them.
>> This transmitter puts-out 10 watts- not much.
>> In mine, one of the supplies has bad iron.
>> I pulled the fuses and the vibrator on the bad side.
>> The other side is operating well.
>>
>> I can't imagine this 10W rig needs double the current
>> that one of these supplies can source.
>> Manual has no explanation.
>> Does anyone know why this unit has dual supplies?
>> Does the BC-223 really need the extra current
>> or is it some kind of "redundancy" thing?
>>
>> 73 DE Dave AB5S
>>
>
> Robert Downs - Houston
> wa5cab dot com (Web Store)
> MVPA 9480