[AMRadio] DRIVER XFMR UPDATE

[russ dworakowski]

try  antique electronic supply  for  100uf caps work  just fine  in
this  rig  Russ






>From: "MIke Wells" <mwells at gcea.coop>
>Reply-To: amradio at mailman.qth.net
>To: <amradio at mailman.qth.net>
>Subject: RE: [AMRadio] DRIVER XFMR UPDATE
>Date: Fri, 21 Feb 2003 16:36:38 -0700
>
>I have changed the bias supply caps but didn't mess with the LV 
>multisection
>cap in the can and didn't have any replacements for the high voltage caps.
>The cathode bypass caps are easy to find so I always start with them. I am
>at some what of a loss as to where a person can find replacements for caps
>in the 300 working voltages and on up? Is there a big supply out there?
>Particularly like the 150mfd 450wv high voltage caps, I don't know where to
>find them so I may pick some stuff up at a swap meet but they are probably
>as bad as what is in the rig. Where is the best source?
>
>Mike
>
>-----Original Message-----
>From: amradio-admin at mailman.qth.net
>[mailto:amradio-admin at mailman.qth.net]On Behalf Of russ dworakowski
>Sent: Friday, February 21, 2003 11:51 AM
>To: amradio at mailman.qth.net
>Subject: RE: [AMRadio] DRIVER XFMR UPDATE
>
>
>Mike there are  other caps  that  need replaced  as well.  remember  this 
>is
>   50  years old.  Cathode bypass caps in  the speech amp,  also
>electrolytics in the bias supply and  LV and  HV supplies are all culprits
>down the road.    Change  these as a matter of  preventive
>maint.  Russ.
>
>
>
>
>
>
> >From: "MIke Wells" <mwells at gcea.coop>
> >Reply-To: amradio at mailman.qth.net
> >To: <amradio at mailman.qth.net>
> >Subject: RE: [AMRadio] DRIVER XFMR UPDATE
> >Date: Thu, 20 Feb 2003 16:38:59 -0700
> >
> >Hello guys,
> >Just thought I would again say thanks to those that helped with comments 
>on
> >replacing the driver transformer in my DX-100. Bob, W4WSZ sent me out the
> >exact replacement and I now have it in the unit and playing.
> >
> >A couple interesting things I found was the new 5V4 low voltage rectifier
> >tube was bad, must of seen too much current. After replacing the 5V4 and
> >testing the circuit I saw the 12BY7 was shorted and looked more like a
> >light
> >bulb than a tube. I went looking and found the 680 ohm cathod resistor 
>was
> >burned open. Now I wonder if the resistor failed first, taking the 12BY7
> >then smoking the driver xfmr causing the 5V4 to die. Or maybe it all
> >happened when the xfmr went up in smoke. It is back on the air and Chuck,
> >WA0ZHH and Lonnie W0GPZ said it sounded good.
> >
> >73
> >Mike
> >W0FD
> >
> >
> >
> >
> >_______________________________________________
> >AMRadio mailing list
> >AMRadio at mailman.qth.net
> >http://mailman.qth.net/mailman/listinfo/amradio
>
>
>_________________________________________________________________
>Add photos to your messages with MSN 8. Get 2 months FREE*.
>http://join.msn.com/?page=features/featuredemail
>
>_______________________________________________
>AMRadio mailing list
>AMRadio at mailman.qth.net
>http://mailman.qth.net/mailman/listinfo/amradio
>
>_______________________________________________
>AMRadio mailing list
>AMRadio at mailman.qth.net
>http://mailman.qth.net/mailman/listinfo/amradio


_________________________________________________________________
Add photos to your messages with MSN 8. Get 2 months FREE*.  
http://join.msn.com/?page=features/featuredemail