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Needem Schematic SCP Amature Amplifier like a Palomar Skipper

Jay Mojave

Sr. Member
Nov 17, 2015
323
610
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Hello All: Looking for a schematic / diagram for a SCP Amature Amplifier Tube Amp, Uses one 8950 Driving 3 8950 Tubes. I have the Palomar Skipper diagram that uses the same tube design, but would like the SCP diagram, I believe its the same as a 321 amplifier. Will cover costs. Jay
 

AudioShockwav

Extraterrestrial
Staff member
Apr 6, 2005
7,684
5,670
593
Sierras Near Yosemite National Park
Jay, I remember my brother had one of those amps, I really thought it had 1x3 - 6kd6 tubes in it.
Years ago, ,
I will look around and see what I can find.


73
Jeff


Jay
I gave up on the Buddie Base.
He is not going to let go of it.....
 

Jay Mojave

Sr. Member
Nov 17, 2015
323
610
103
70
Yo Jeff thanks a million. The Palomar Skipper 300 diagram talks about the use of 8950 and 6KD6 tubes using different filament voltages, 13 Volts for the 8950, and 6.3 volts for the 6KD6 tubes. So maybe the 321 amps did the same thing? Jay
 

nomadradio

Analog Retentive
Apr 3, 2005
5,565
8,203
573
Louisville, KY
www.nomadradio.com
The 321 was a "PAL" product. Pretty sure the guy who ran it was named Frank Sacks. Used the CB handle "baggy".

I have heard that Palomar built his amplifiers, but didn't use his designs for their own "Palomar" branded stuff. I remember someone saying that Swan built some of his amplifiers, but I'm skeptical.

I suspect the choice of tube between 6KD6 and 8950 was more likely driven by cost. Whichever one they could get a skidfull cheap would determine how those pins on the sockets were wired for a particular production run. Only affects pin 1 and 12. The rest of the socket is wired the same for either type.

The 321 diagrams are posted here: http://www.cbtricks.com/Amp/pal/321/index.htm

73
 

Jay Mojave

Sr. Member
Nov 17, 2015
323
610
103
70
Thanks Nomasradio: Got all the little things working. Will run some drive thru it today to see what happens. Thanks again.

Jay in the Great Mojave Desert
 

Jay Mojave

Sr. Member
Nov 17, 2015
323
610
103
70
Hello BJr and Nomadradio: Found a diagram for the 321 almost the same with small differences. I will post it here in a while.

The 321 Amp turns out to have shorted filament winding getting the power transformer well over180 F degrees. While just setting there with tubes removed and in STBY Mode you smell the transformer, charming.

Found a almost brand new Palomar Skipper 300 under the work bench, I will put the expen$ive 8950 tubes in it and give it a try, its transformer runs cold while plugged in. And has a 13 volt filament voltage, so we will see.

A real shame the sweep tubes are so much money. I just need a amp for camping with 100 watts of dead key feeding a Interceptor 10K up about 30 feet for camping in the Mojave Desert. Keeping track of 50 plus Jeeps on a Jeep Club Poker Run as I need my signal to bend around mountains, hills, and valleys. A 100 watts will give about 14 dB increase, plenty. Also having to replace 4ea $D1446 and capacitors in my 41 year old M350 amp, what a battle for just a few watts extra.

Contacted a few amp builders and got not so great response, everything from over rated power output quotes, ("I know what iam doing" yeah right) to no reply. Great!

Jay in the Great Mojave Desert
 

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