My very good friend in New Jersey has been extremely busy.
He works for one of the big three TV networks. He is
a private guy - so in respect to him - I won't even say which
My very good friend in New Jersey has been extremely busy.
He works for one of the big three TV networks. He is
a private guy - so in respect to him - I won't even say which
network. He is a great guy, though, and a really good RF
and computer man. You won't ever see him on here, he is
just too busy and getting busier all the time.
BUT - he told me he is getting ready to send my LPB RC-6A
carrier current transmitter back to me. He never got a
chance to work on it. It was the new job at the network that
made his life a lot busier.
So cross your fingers. I hope he is really able to do it. (We
are very close friends so if there is another delay, I completely
understand.) In fact, at this point, time still doesn't really matter -
but if it comes back it would really be cool.
So cross your fingers anyway. I have reason to believe the RC-6A
will be back very soon, and then I can start working on it.
I think I'm pretty sure what I need to do, and the steps involved.
It will take time.
But I hope to have that glowing box sitting on top of the Gates Board,
soon.
Bruce, DOGRADIO STUDIO 2
My friend in New Jersey had my RC-6A CC transmitter
on the bench, and he checked it out thoroughly.
He said he would ship it back to me in a couple
of days. He is writing up a detailed tech report
as I send this message.
The transmitter does have one serious problem.
Although it runs full power on 860 kHz (the crystal
frequency) there is a broken adjustable slug on the
inside. There are two slugs - one is OK, and one
is broken. I don't know how long this problem
has been present. Moving the frequency may be
more difficult than previously thought. But we'll see.
I'll just be glad to see it again. Despite it's troubles,
this thing is a part of broadcast history - like my Gates
board, and I really like the transmitter a lot.
My friend marveled at the beautiful modulation transformer.
He said that transformer itself might be worth $300 dollars.
Not that I intend to sell it.
Also, he recapped the unit. And just for fun - well there was
hum on the carrier - so he fed the tube heaters with a variable
DC supply, and most of the hum went away. So he thinks one
of the 6AL11s may have a cathode to heater short, although he
is not sure.
So, we'll see where it goes.
Bruce, DOGGRADIO STUDIO 2
Finding out if there is a short between filament and cathode without replacing the tube is to simply isolate the filament voltage from the unit's power supply..ie use a different power source for the filament (AC source through a 1:1 transformer).
This technique was used a lot in the CRT business to solve cathode to heater shorts using a mere 4 windings around the HV transformer core and hooking the two ends of that wire right up to the filament leads after cutting away the foil trace on the CRT board.
Works well for regular tubes with the same heater to cathode short.
RFB
That's good to know. Well, I guess I'll be
doing a lot of things when this RC-6A
comes back. I guess we'll have a lot to
talk about.
Thanks again,
Bruce, DOGGRADIO STUDIO 2