[TMC] (no subject)
D.Hepworth
[email protected]
Fri, 27 Dec 2002 23:46:41 -0800
Hello to the group, I was taken away from the computer for a few days, Now
I can and finally finish this story.
I had realized that the gpr-90 was very mis-aligned, someone had adjusted
all or most of the slugs and capacitors,
it was not hearing even the strongest SIG's.( local Broadcast stations ) I
do not have a sig generator , so was lost on how I was going to go about
getting this receiver up and running to specs.
I didn't want to just turn slugs and mess it up more than it was.
I decided I would re-paint the cabinet, There was some minor surface rust on
the lower shelf of the cabinet , paint was flaking off . You'll never find
any radio today that could stand up to the environment as this radio did, a
true statement of the craftsmanship and quality of these fine radios .. I
found that Machine Gray spray paint was the closest I could get out of a
can.
The speaker front grill cloth was very dirty and stained, We have fabric
store in town and I couldn't believe That I had found a perfect match for
the grill cloth.. I did this restoration in about 2 hours.. looks great now.
I will match the factory paint in the spring when I can get outside to paint
it again.( Snow 6" here -15 c)
I was told of a good website where there are schematics for these radios, I
wrote earlier that I had gone to BAMA for the schematics and Alignment
information.. I thought of it later, it was the TMC WebPages that I equired
the info.
I printed out the information I needed to start the project of getting her
going again, at this point I was getting noise from the receiver so I knew
that the audio circuit was good.
I listened with my headphones on and the volume turned all the up, but heard
nothing coming through..
I spent hours cleaning the inside ..years of dust and grime build up.
Surprised that all those years under those trees it really wasn't all that
bad. I've seen dirtier radios in some peoples shacks hi.. There was still
had a couple of the locals residents running around inside.
The underside of the chassis was factory clean, no mods, none of the caps
were sweating..
The Gear driven dials work smooth as silk, The only problem switch was one
and that was the R.F. Selectivity it just needed a little grease and a few
rotations and it was snapping and clicking like it should feel and sound.
At this point I was frustrated that I didn't have anyway to get a sig into
it ( sig generator ) I was talking to a buddy on 80 meters one night and
happen to have the GPR-90 on and tuning the Megacycle dial , I happened to
hear some sideband station that was off my freq. I was transmitting on, as I
tuned closer to the station being heard I realized it was me .Even at 100+
watts output so close to the radio It still was not hearing better than
S1.. I adjusted the antenna trimmer knob in the front of the rig and the
sig came up a S unit or two.
I was very excited about hearing me, I usually don't like my voice , but
this time it was a Heavenly voice.. Hi..
I signed off with my friend after telling him I had heard myself on the
gpr-90 and wanted to get to work on her.
I then proceeded by connecting my Transceiver into a dummy load and placed
it into about 25 watts out.
The alignment procedure is very straight forward and doing it according to
the book it came together very nicely. Sigs started to jump out at me as I
proceeded forward. Each band segment improved as I whistled while I
worked...
I have a Freq. counter , so I plugged that into the IF output in the rear of
the radio ( this output connection is used for the GSB-1 SSB adapter.. I
read 455.35 kc + - . So I knew everything was fine there.
By the way the lightbulbs still lit up.. After going through the alignment
about 5 times and monitoring the components for smoke or excessive heat
build-up I found nothing wrong with this beautiful Gray box.
All I can say, after all these years this Radio truly is a statement , like
many of the older hand crafted / hand built radios of that period ... is
that there is only one way to build a keeper and that is with care and
quality components.and quality workmanship. I've put approx. 40 hours into
this radio and hope that it will give me many years of listening pleasure,
something you can't get out of the new rice boxes.
I listen every night to AMers on 80 meters and a few old radio shows
re-broadcasted and there's nothing like listening to them on my GPR-90
Speaker.. wonderful audio.. This is what they mean by working the bugs out
of the old set. I'm still seeing a few spiders coming out on occasion and
they seem to have a bit of a tan... Hi. I just let them wonder out and find
a new home ...
I'm looking for a GPT 750 now to match this great receiver , maybe I'll
check with that swap and shop again.. who knows what I will find under the
next Pine tree, hi.
If anyone would like a picture of the way it looks now, I would be glad to
E-mail you a pic..
Unfortunately I didn't take a picture of the radio when I Picked it up..But
just imagine sitting under a tarp for 10 years and you can see for
yourself..
Thanks for the E-mails about wanting to hearing the second half..
Keep those tubes glowing . --... ...-- 73
De : Dennis ve7dh [email protected]
Good morning & afternoon to the group,
I have to pass on this interesting story how I just acquired my GPR-90 and
it's speaker, I had listed on are local swap & shop that I was looking for
a GPR-90 receiver .
I expected 0 response from my ad , When I finished with my listing a fellow
Ham north of me (60miles )
comes on and says he has a GPR-90 for me.. But it's been kept under cover
for the past 10 years outside
( I thought he meant in a shed )... I talked to the gentleman about the
radio and it's condition It was apparently
turned on some 10 years back but the fuse was popping ,
I arranged to pick up the radio the following day with a fellow ham . We
arrived at the radio's home , pulling into the driveway and the fellow that
owned the radio was standing under a pine tree with a tarp at his feet!
I looked at Bob and he looked at me and we smiled and thought , No it can't
be there?
We proceeded to walk over to the pine trees and introduced ourselves . I
looked down and commented is this where the radio now lies?( I expected to
see R.I.P written on a tombstone under the tarp).. he said yes . We then
lifted the double tarps ( 2 tarps for anything past 5 years outside storage
hi ) The radio was sitting on the ground , I lifted it up with some fear
that a snake would crawl out from under it, but only pine cones and
thousands of pine needles hanging off of it and falling out of it..At this
point many of the local residents started to evacuate ( spiders & and other
beasts ) The speaker was kept in the house ( very glad of that ).. I took
the radio over to the tailgate of the truck , and tried the main tuning
controls, they we silky smooth still and had a solid feel to them and all
the other switches still had a nice snap when you turned them. The two main
kHz & MHz windows were still white and not gone to that yellow gold color ,
Maybe spiders do windows? hi.
After getting the radio home (it was kept outside for 2 hours to shake out
the cobwebs and the contractors , pine cones & needles .
I decided that the only way to find out if I had a working radio was to plug
it in fire up, holding my breath I turned it on and the fuse blew, this was
good, I pulled out the voltage RECTIFIER ( 5U4G ) AND THE 6V6GT v reg. )
They were shot, I replaced them and pulled all the other tubes out and check
them all.. they all checked out 70 to 80% So I knew I could proceed to fire
it up again.
I turned it on and behold there was light...But I heard now signals at all I
did not have book with radio , but found the schematics and alignment chart
on the internet..(BAMA ) I had the radio on it's side to monitor any
possible smoke signals, Continued after lunch..........