DX-60 Repair Adventure, or DX-60 only Works on its Side

[Freeberg, Scott (STP)]

Over the past several of years I've casually collected an HR-10B, HG-10,
DX-60B but I haven't gotten around to assembling the station yet.  

Friday I got the bug to get the Heath station up and running so I moved it
down off the shelf and into the one of the operating positions.

Last year I realigned the HR-10B receiver, so I didn't have
to do anything with it other than wire up the mute contacts to the
antenna relay. I was listening to 40 meter CW while I was
working on the transmitter.  That HR-10B sounds pretty nice and was probably
a nice beginning ham receiver.  It sounds alot better than some of the junk
that was sold as a 'ham receiver'.  The Conar 500 comes to mind, or the
Ameco R5.

I hooked up the VFO and TX and just fired it up.  There was very little
grid current and the frequency wobbled with out any provocation, so I put
the TX on the bench and opened it up, set it upside down. I checked the voltages and they were 
good (at where I was measuring them... hint hint).  Then checked the tubes and the 
6146 was bad so I replaced it.  I was now getting grid current.... ok.... that was
easy.  I had a crystal in and I listened to the signal on the receiver.  The oscillator was
stable and sounding very
good.  I turned it over, closed up the PA cage, and went to measure power but got nothing.
No grid current again.  Huh?

So I set it on its side to start probing and got grid current right away. 
I started tapping around the chassis and found it was intermittant.  It seemed to be the worst
when I tapped on the PI Network box, so I shut it down and pulled the box off the chassis.
I found a burned up silver mica on the last stage, but that wouldn't account for the
intermittent problem.  I replaced the silver mica and then touched up all the solder
joints in the box, reattached it, powered up the DX-60, and it was still intermittent. By the
way, those PI filter box screws such are a bugger to get at.... 

I was now tapping under the chassis with the Red Heathkit plastic nut driver, tapping components, 
sections, and I found an unsoldered joint.  AH HA.  Soldered it, turned it back on, and... and...it
was still intermittent.  

By now I'm starting to notice that it often works on its side but it never
works when its sitting down on the table...  Up/down, Up/down, work/no work :))) With the TX on its side,
I continued tapping but I couldn't find a sensitive area.  I got down on the
floor so I could peer up under the chassis as I lowered it down to the table, and I saw a brief ZZZtttt.
It was in the high voltage section, a lug had a couple of HV connections on it, and one of them
was not soldered.  It was hidden under the soldered joint above it. So what apparently was 
happening was the connection was made when the TX was laying 
on its side or upside down, but when the TX was placed flat on its feet, the weight of the power 
transformer tweaked that
joint slightly, opening the connection... Sheesh.... So I 
soldered it up and that was the end of
the intermittent problem.  After than I went through and looked at the rest of the connections,
hunting for any more unsoldered joints.   I should have recapped the high voltage electrolytics
but I didn't have the right value so I'll order them from Mouser.  I also retighted every screw and
nut in there, relubed up the rotary switches, a little DeOxit here and there.

I just started going through the HG-10 VFO before calling it a day.  Maybe I'll get to that this 
week and have the classic Heathkit station on the air by the weekend.  I love CW and hope to have
a ball with this station on CW.  While I hear an occasional DX-60 on AM, I'm not
that much of a masochist  :)

I thought you guys would get a kick out the sideways adventure.

Did Heathkit ever give away blank QSL cards for Novices to use?

Last night I closed up the HG-10 VFO, hooked it all up, and tested it.  The TX/VFO signal sounds
great, stable, clean.  I called CQ a few times on 40 with no response and called it a night.

73, Scott WA9WFA

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