[Heathkit] SB-200 issues.

[Peter Markavage]

Read through this info. There are lots of tips and solutions to a number
of problems have plagued SB-200's over the years.
http://www.xs4all.nl/~pa0fri/Lineairs/SB200/sb200eng.htm
Pete, wa2cwa
 
On Sun, 03 Jun 2007 21:58:54 -0700 "Kenneth G. Gordon"
<kgordon2006 at verizon.net> writes:
> On 3 Jun 2007 at 21:10, Ian wrote:
> 
> > Ken,
> > 
> > It sounds like it's time to get out the ohmmeter and start tracing 
> the
> > entire circuit.  ???????
> 
> Well, I found one problem that is fairly interesting: RFC-3, the RFC 
> 
> which is across the antenna connection for safety, appears to be 
> MUCH 
> larger than 1.1 mH. It looks a lot like a 2.5 mH or larger choke. 
> When I 
> disconnected that so that I could check to see if the bandswitch was 
> 
> adding the extra loading cap on 80, now the rig loads properly. At 
> the 
> bottom end of 80, the loading cap is still open a bit.
> 
> I wonder what else I will find?
> 
> > 
> > Otherwise it would seem that you are in for a long series of 
> finding
> > the problem only to have another pop up down the stream.
> 
> Thanks, Ian. However I have gone pretty much completely through the 
> 
> circuit. It IS pretty simple, after all.
> 
> It appears that one tube, the one that wasn't lighting, is not 
> drawing the 
> proper current. All grid resistors seem to be OK. I am wondering if 
> one 
> of those little 200 pfd mica grid bypass caps is open.
> 
> And the difference in filament brightness still bothers me...one 
> tube is 
> considerably brighter than the other.
> 
> Ken Gordon W7EKB
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