Up behind the controls there is nothing, really, just a big old capacitor on the contour pot (“tone” on the schematic) and a resistor across a couple of the inputs.
The tubes in my pictures are, from left to right, the rectifier, the two big 6l6 tubes, and, on the far right in front, the 5879, and in back on the right the 7199.
The 5879 is a pentode that was apparently used on some Gibson amps of the time, and some NOS are floating around for 50 bucks!!!
But I got my for 8 bucks.
The 7199 is a triode-pentode, apparently used in hi-fis, also hard to find, 35 bucks or so for NOS.
Info sheet here:
http://www.triodeel.com/7199.htm
I bought my replacements here - really nice people:
http://www.tubesandmore.com/
Well, I wish I had the training to fix this up, but someone else will have to do it.
I’d really like it really entirely redone top-to-bottom…but that probably would cost too much…
Oh - I have confirmed it - someone made the front the back and vice versa - perhaps they wanted the controls in front for access? To look cool? Any way, I can switch it back easily.
Any idea what a reasonable cost would be to get this done by a pro?
I, personally, don't really want to get electrocuted.
The way you don't get electrocuted, is...
Whenever you work on a Hi-Voltage Tube circuit, you do everything as if you lost your left hand..
If you are right-handed.. OR..
right-handed if you are a south-paw..
Sorry..
I messed that up.. But.. you know what I meant.. hehe
You only get a shock if you attempt to pass hi-voltage through your body..
Well..
Bill..
Hi TomS:
We confirm… that’s the Amp Schematic… NO Tubes up on the control panel… All the tubes are on the Chassis on the floor of the amp… Too bad the the photos of that amp don’t show in any detail how the speaker baffle panel is constructed… If It’s just a plywood panel or, if it had some depth to the baffle panel… If it has some depth then there would be a panel that has a border around the edges of the Baffle panel… You know… ??
Would you have any objections to pulling the chassis out of the cabinet and posting some photos of the component side of that chassis? I’d like to see just what it looks like… If enough detail can be captured, it might show if any work has been done on this machine… I’d say by the appearance of this box, that the amp has seen stage use… I’ll bet this amp has a few war stories to tell…
Bill…
I keep wondering which great Flint area band in the 60s used it. Maybe it was Mark Farner’s when he was just starting out. 
What do I need to know to pull out the chassis? should I do the resistor thing on the plug?
I keep wondering which great Flint area band in the 60s used it.
Maybe it was Mark Farner's when he was just starting out.
What do I need to know to pull out the chassis?
should I do the resistor thing on the plug?
Since there's a cap right in the line, it certainly wouldn't hurt but likely unnecessary.
I used to always have an alligator clip lead with a 470 ohm, 1/4 watt resistor soldered in line covered with heat-shrink tubing. Clip one end to the chassis and the other to a long screwdriver with an insulated handle. Slide the chassis out and poke around the caps with the screwdriver tip. Since that thing has a low parts count, just spend a few minutes poking around. It's the caps that can getcha though.
UJ
Hi Unblown_Jonson:
That’s nice to do, before poking around in with your fingers, inside a Tube Amp… For those Tube Amps that have standby switches, the operator should adhere to a “Turn-on and Turn-off” sequence…
When turning the amp ON, always turn the power switch on first, wait two minutes, or whenever wanting to play the Amp, then turn the Standby
Switch, ON…
When turning the Amp off, Always turn the Power Switch OFF, wait two minutes, then turn the Standby Switch OFF…
If you’re playing a Bar room job, you never turn the power to the amp off between “SETS”…
Leave the amp power turned ON, for the evening…
Just use the Standby Switch, ON-and-OFF…
Following that sequence will always leave the switches in the proper position for the next time you turn the amp on…
When removing the chassis from the cabinet, always turn the Standby Switch on for two minutes before touching any components with your fingers…
By adhering to that principal, most-if-not-all residual voltage will be discharged, from any capacitors…
OoHh YES…
Always unplug the Power Cord from the power source before you remove the chassis from the cabinet…
Then …
when all is “Clear” and you begin to diagnose the circuits, plug the power into a source of power BUT, with an incandescent light bulb in series with the incoming mains power…
The Wattage of the light bulb depends upon the Power Rating of the Amp, under test…
A 6L6 type amp should have a 100 watt bulb as the limiting factor… A 6V6 type amp should have a 50 watt bulb in series with the incoming mains power…
BUT…
again, that’s with a standard 115 - 120 volt North American type of power source…
220 - 240 power source…
1/2 of the wattage rating…
25-and-50 watt bulbs…
?
Well…
There is no secret about being shocked with stored up DC Current…
“Once Shocked
…
Twice Careful”…
It’s not as lethal as the “kids and uneducated service guys”, talk about…
No One likes to tempt fate, though…
It’s nice to get a bolt of “Juice” once-in-a-while…
IT Keeps you from getting Blaz-EH or going asleep, when having fun…
You Know…
lol…
hehe…
Every time it happens,
you’re never anticipating IT, to happen… IT’s never the same way…
Bill…
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[edit]
Quote: (TomS @ Nov. 08 2010, 4:30 PM)
I keep wondering which great Flint area band in the 60s used it.
Maybe it was Mark Farner’s when he was just starting out.
What do I need to know to pull out the chassis?
should I do the resistor thing on the plug? .
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I’ve heard about these amps over around here… However, I don’t recall ever seeing one of them needing any type of repair…