[MRCA] BC-348 Help

[DSP3]

Brian, Your 10A supply is quite sufficient, assuming all else is OK with 
the radio.  If your radio is other than a J, N, or Q model (those are 
more reliable, capacitor wise) you may want (need) to do a re-cap, to 
those include inside the 4 modules, the crystal filter and BFO cans. 
Capacitor shorting or leakage can be detected by measuring the B+ 
current.  It should be from 50 to 80ma under operation.  More than 80ma 
at 220v indicates potential excessive current. Current can be measured 
at the dynamotor connection strip. Simply remove the B+ wire and insert 
a milliammeter.  Bring the radio up with a variable DC supply, if 
available.  If not, then just monitor the current and shut down if 
something is untoward.  I have a dynamotor simulator chassis that I 
mount in place of the dynamotor such that I can monitor filament and B+ 
draw from an external power supply.  The above is what I go through for 
each BC-348 I service.  The re-cap procedure is not too tough but does 
require time and attention to detail.  I did an article for ER magazine 
that goes through all this.  Its sometimes pretty amazing how these 
receivers come to life after some TLC.  If I can assist with info, 
please let me know.

Jeep - K3HVG

On 2/9/2019 2:36 PM, Brian Roberts wrote:
> 
>
> Hello Gents--
> I've acquired a BC-348R and it appears to be unmolested.   It still 
> has the dynamotor in it and I'd like to get it going again in its 
> original mode of operation with the dynamotor.   I'd like to solicit 
> opinions and help from guys who have gone down this road before as far 
> as things that must be done, and any hints and kinks on how to do 
> them.   I'm sure the dynamotor will have to be cleaned and lubricated 
> for openers and that will be a new task for me. Another area of 
> concern is how much amperage will be needed to start and then run the 
> set?   I've read anywhere from 8 to 50 amps!    I have a 10 amp 24 VDC 
> power supply available, but I don't think that will do the trick to 
> start the dynamotor. I'm thinking about putting two 12 volt batteries 
> in series to start the set, and then once the dynamotor is up to speed 
> switching over to the power supply.   Again, I'd like to solicit 
> comments on that idea.   Thanks.
> Brian K9VKY
>
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