[ARC5] Replacement power xformer for a BC348 or other mil receivers

[Don Sanders]

I found small transformers at Home Depot used for control voltage on the
furnace, I believe. 24 volts at about 2 amps and $12.00. I used two to make
a PS for my BC455. Should be good for other filament used also.
Dr. Don W4BWS

God Bless All



On Mon, Aug 8, 2022 at 1:53 PM <releazer at earthlink.net> wrote:

> I only own eight BC-348 receivers and two BC-342's, but in my opinion
> you'd be better off building a separate external power supply.
>
>
>
> One BC-348 I bought worked right out of the shipping box and examination
> revealed that a previous owner had followed the Surplus Conversion article
> exactly, using a 300V B+ transformer with separate 6V and 5V filaments
> windings, a 5Y3 and a classic capacitor and choke filter.  Even without
> replacing the 5Y3 with solid state rectifiers this still left the B+ much
> too high.  The BC-348 used 220VDC from the dynamotor and will run happily
> with a lot less and with less stress.  I added power resistors in both the
> AC line and the B+ line to get the voltage down to about 200 VDC and
> rebuilt the mounting plate for the internal power supply into something
> less likely to produce a disaster.  They had used the original dynamotor
> mounting plate for the power supply and I replaced that with an AL plate so
> I could create a dynamotor pack some day; hope you are as lucky.
> Unfortunately they had used the original front panel ON-OFF switch for the
> AC line and I did not like that much, installing a inline switch on the new
> power cord.
>
>
>
> Good luck!
>
>
> Wayne
>
> WB5WSV
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: https://www.qsl.net/donate.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20220808/55a047f7/attachment-0001.html>