[Milsurplus] BC-342 High B+ Current

[Al Klase]

Hi Mack,

These radio's are full of .05 uF and other value Bakelite-cased caps 
that probably say Micamold.  They come in two varieties: those that are 
leaky and those that are going to become leaky shortly.  The only proper 
course is to replace ALL of them with mylars or ceramics.  This is not 
an easy deal, as you need to remove and open each of the front-end 
modules and various IF cans etc.  A couple of the front-end caps can 
only be removed by cutting one lead and wiggling the cap until the other 
end breaks free.  Fortunately there are places to connect new smaller 
replacements.

These are pleasing radios once properly restored, but be prepared for a 
chore.

You might want to read this info on my website:  
http://www.skywaves.ar88.net/commrx/Maintenance/Receiver_Maintenance.html

Good luck,
Al

Mack McCormick wrote:
> I'm restoring a BC-342 (original AC power supply). I've replaced the electrolytics in the power supply and B+ is normal. I checked the current draw and it's drawing 150 MA. Obviously too much current. I noted that all the B+ and Screen filter caps are 0.5 mfd oil filled paper with three caps in each metal case.
>
> For those of you who have restored one of these rigs is there a "usual suspect" that causes the high current draw? Do you usually replace these caps with ceramics? Is there a cosmetically best way to replace the caps since the originals are no longer made? All guidance/thoughts are appreciated.
>
> By the way, I successfully restored my BC-348 and am using it on the air daily with my ART-13. Thanks to those who offered tips on that restoration. The final key was to properly bias the cathode on the audio output tube.
>
> 73,
>
>  
>
> Mack
>
> WB4MAK
>
>
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ------------------------------------------------------------------------
>
>
> Internal Virus Database is out of date.
> Checked by AVG - www.avg.com 
> Version: 8.0.238 / Virus Database: 270.12.25/2109 - Release Date: 05/11/09 16:14:00
>
>   

-- 
Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net/