Bassman Build-up (a bit long)

[guitardude57]

There is no way I would wire up the AC power, switch and fuse like that drawing. The common and hot are crossing at the power switch....wow.

You should not fuse the common, you fuse the hot (black).

Look at the D-lite with relays drawing I'm including. Better power layout, with a complete disconnect with the neutral and the hot on a multi-pole switch. Also a good idea to spread the standby juice on more than one switch-leg too.

Go ahead and do the relays, it will be worth a couple extra wires and related. There are many ways to skin that cat. Doug Hoffman, (el34world.com in the Tube Amp Building - Tweaks - Repairs section at the top) recently put together a nice small relay board and PS board that could fit in just about any amp with no difficulty. And more than reasonable price. Cheap. The board set can be done in 5V or 12V.

[EL34]

Thanks for the mention on the relay boards
I tried to keep the price as low as possible on the two boards

Here's a page link for anyone interested in them

http://www.hoffmanamps.com/MyStore/catalog/parts20.htm

[dezmoduo]

I like the idea of breaking the neutral and hot across 2 legs instead of one. I'll also follow the link for the relay boards and consider including that in the build. At this point I might as well and I have the room.

Guitardude, what is the DPST switch between V3 & V4? Half power switch?

I'm not Gary from New Sensor. I'm just an average picker from NYC, newbie wanna-be amp builder. I've got SS combo amps just dying to be converted.

Time to process the new information

Gary

[guitardude57]

I guess I ignored that switch...

It looks like a pentode/triode switch, but it is missing some resistors to not hammer the screens. I'm sure someone will chime in.

The half power switches I have seen basically, nearly ground the cathodes with a couple of resistors and an LED to the inside tubes of a 4 holer... ultimately giving you half power. So they are not entirely grounded, but enough to shut them off.

I put up the drawing to show a better power switch and standby wire up.

The other drawing would have blown out your breaker in your house.

[guitardude57]

Here is a Mark Huss drawing of a 1987 circuit with the pentode/triode switch.

[guitardude57]

Your are welcome Doug!
The relay boards you have done, are wunnerful!

[ToneMerc]

Guitardude, what is the DPST switch between V3 & V4? Half power switch?



Gary

The OT has primary taps for both 6V6(8k)and 6L6(4k) tube types.

TM

[guitardude57]

Okey dokey, I knew someone would know...

[dezmoduo]

I managed to wire the AC line, rectifier board, power switch, standby switch (both DPST), the bias test ports, impedance switch (4/8/16) and speaker jacks.

The selector switch kicked my butt. I have the Mouser #105-SR2511F-43RN, and the terminals are just really tiny and the OT leads aren't. Glad I bought four of them. (looking down the road I am). And there are plenty of terminals to choose from even if I buggered one or two. This is the kind of moment I should have stopped and posted a question, but no.
The OT leads weren't going through the terminal slot. I took snippings from the PT leads (proper colors Y/G/Or), that did fit and soldered 3 short leads onto the switch plus one for the run to the speaker jacks. I also dropped heat shrink over each terminal. Then I mechanically joined the OT leads, soldered and heat shrink (shrunk?) to the switch extensions. I spent 10 minutes with my DMM to convince myself that all that wire wasn't going astray. And the meter showed a short on each position of the switch. There's my clipboard with the OT schematic right on top. A common coil with multi taps. I finished the speaker jacks and packed up the gear.
On a closing note, brown or otherwise, first build and all that stuff aside, being able to get each lead, connection, component to fit, soldered, and dressed to kill at the level that I see in so many photos here and elsewhere is all the more staggering. Hats off to all the pro's and craftsman. The bar is set quite high.

Gary
itslongcausethatsthewayItypeit.

[rogb]

I managed to wire the AC line, rectifier board, power switch, standby switch (both DPST), the bias test ports, impedance switch (4/8/16) and speaker jacks.

The selector switch kicked my butt. I have the Mouser #105-SR2511F-43RN, and the terminals are just really tiny and the OT leads aren't. Glad I bought four of them. (looking down the road I am). And there are plenty of terminals to choose from even if I buggered one or two. This is the kind of moment I should have stopped and posted a question, but no.
The OT leads weren't going through the terminal slot. I took snippings from the PT leads (proper colors Y/G/Or), that did fit and soldered 3 short leads onto the switch plus one for the run to the speaker jacks. I also dropped heat shrink over each terminal. Then I mechanically joined the OT leads, soldered and heat shrink (shrunk?) to the switch extensions. I spent 10 minutes with my DMM to convince myself that all that wire wasn't going astray. And the meter showed a short on each position of the switch. There's my clipboard with the OT schematic right on top. A common coil with multi taps. I finished the speaker jacks and packed up the gear.
On a closing note, brown or otherwise, first build and all that stuff aside, being able to get each lead, connection, component to fit, soldered, and dressed to kill at the level that I see in so many photos here and elsewhere is all the more staggering. Hats off to all the pro's and craftsman. The bar is set quite high.

Gary
itslongcausethatsthewayItypeit.

Gary, good to see you are getting on OK.
For future reference, this is a really good impedance selector from Mouser. I use it in all builds now after making the same mistake as you.

633-HS13Y

http://uk.mouser.com/Search/ProductDeta ... y633-HS13Y

[Structo]

+1 on that switch

[dezmoduo]

That is a switch of beauty.
Noted and saved. Heater wires tonight.

Gary

Edit: The heater wires could not go along the back floor. They were mounted up, over and across.

[dezmoduo]

Am I imagining things or are the 5uf 25v axial caps (3) on the preamp board difficult to find? They seem to be because I'm shopping eBay for them!!

Not on the BOM so I didn't check them off when they didn't come in.


Gary

[M Fowler]

Yeah the 5uf 50v are common but not the 25v.

[sepulchre]

Found these at Newark: http://www.newark.com/vishay-sprague/te ... /dp/18F524
Will they work?