Tech Issue

[steve_k]

Not sure what causes this, but I was checking the bias on the tubes and noticed 135V PV on the bias rite with the amp on standby. It is barely audible, but it is not right and is bugging the piss out of me. Not to mention there shouldn't be any volts running around the tubes on standby for power up and power down and when working on the amp. Looked for anything obvious around the pins and wiring from standby switch to to the first power tube, any stray solder slag or ground. Other than the switch itself, or a cold solder joint, I am not sure what else it could be. Anybody else have ideas?

If anyone talks to Mark, please tell him to get back to me.

Thanks,
Steve

 

[RoidRage]

Mark as to my expierience has been really good aHbout teching the amps over the phone... When I had some questions about stuff he spent a great deal of time on the phone with me while we went over the amp together... Hopeufully he hooks up with you soon Steve.

RR

 

[steve_k]

Mark as to my expierience has been really good aHbout teching the amps over the phone... When I had some questions about stuff he spent a great deal of time on the phone with me while we went over the amp together... Hopeufully he hooks up with you soon Steve.

RR

He might be getting stuff rounded up for the LA Amp Show.

Steve

 

[glip22]

Steve, Did you try just testing at pins 3 & 8 with the + - probes on a DMV to check it? Only your heaters should be seeing volts on standby. Sometimes the probe sockets get flakey. Happened to me.

 

[steve_k]

Steve, Did you try just testing at pins 3 & 8 with the + - probes on a DMV to check it? Only your heaters should be seeing volts on standby. Sometimes the probe sockets get flakey. Happened to me.

I need a pin out voltage chart. I will pull the chassis and check it all again. Its not really audible with amp on. Still, there is some stray voltage. Could be the standy switch is bad and I think it just reverses ground.

Anyway, too busy noodling around with my new Twin Jet that just got here this morning from Rob. The Uber is still the ultimate metal amp.

Steve

 

[thegame]

The Uber is still the ultimate metal amp.
Steve

Respectfully, I have to disagree. I think its clear why

 

[steve_k]

The Uber is still the ultimate metal amp.
Steve

Respectfully, I have to disagree. I think its clear why

Crystal !!!! Let me rephrase....ultimate "production" metal amp. That Natas is bad ass. Just heard some clips last night that Mike sent me.

Steve

 

[steve_k]

Get it figured out yet?

Nah, haven't bothered with it. Will tackle it today. Been too busy playing my new Twin Jet

Have you noticed any voltage on yours when biasing? It shows 135 volts. The standby may just reverse ground on the center tap and short across the tubes. In this case there would be some residual voltage. I will pull it today and get a better look with the DMM. It isn't audible, so I haven't been too bothered.

Having trouble getting through to the Technical Service Department at Cameron HQ

Steve

 

[steve_k]

I have no voltage when on standby... I will try and call Mark tonight about it...

I know he was at the amp show this weekend. Just tell him to PM me on here or email me if he figures it out. I am going out now to pull the chassis.

Edit........

Both leads from the standby switch run around to the first power tube. One goes to ground on the tube socket and the other goes to pin 1 and jumps across to pin 8 then then to the other 3 tubes and dead ends at pin 8 and ground on the last power tube. So, looks like by design, the standby switch lifts the ground on the power tubes and breaks conductivity. So, there will be idle voltage on the pins. Wonder if mine is designed different than the first lot?

Anyway, back in the shell and making ball bashing noise

Steve

 

[steve_k]

I have no voltage when on standby... I will try and call Mark tonight about it...

I know he was at the amp show this weekend. Just tell him to PM me on here or email me if he figures it out. I am going out now to pull the chassis.

Edit........

Both leads from the standby switch run around to the first power tube. One goes to ground on the tube socket and the other goes to pin 1 and jumps across to pin 8 then then to the other 3 tubes and dead ends at pin 8 and ground on the last power tube. So, looks like by design, the standby switch lifts the ground on the power tubes and breaks conductivity. So, there will be idle voltage on the pins. Wonder if mine is designed different than the first lot?

Anyway, back in the shell and making ball bashing noise

Steve

Hmmm. Mark mentioned to me that he did yours slightly different to enable easier biasing? He said yours has 2 bias pots? I wonder if this is the difference and in theory correct?

If it has a second bias pot, it is hidden under the board! Easy would be external test points and bias adjustment....

Its got a tight bias range too without a resistor change. If you had a matched quad in the lower range, you wouldn't get them up there where they smoke!

Steve

 

[jerrydyer]

Idoubt there are two bias points I saw one but ,,,,? Cant imagine him adding one and hiding it without an explaination.

 

[steve_k]

Aw shit. Nevermind....I am such a dumb ass sometime

The Bias-Rite uses pin 8 as a ground reference. With the amp on standby and pin 8 ground lifted to cut power at the tubes, the Bias Rite is going to go ape-shit. Checked all the pins with a DMM and all is well in Cameronville.

Steve

 

[glip22]

Aw shit. Nevermind....I am such a dumb ass sometime

The Bias-Rite uses pin 8 as a ground reference. With the amp on standby and pin 8 ground lifted to cut power at the tubes, the Bias Rite is going to go ape-shit. Checked all the pins with a DMM and all is well in Cameronville.

Steve

Steve, You are not a dumbass!!! I had the same thing happen to me with a probe. Freaked me out when I was reading 720 volts on the plates of one of my amps. Measured the AC from my wall socket and it was like 260 volts. I freaked out and was about to call the electric company when it hit me it must be the meter. Luckily I had another meter and all was well. Pretty funny actually. I was storming around and shut the main power off to the house talking about WTF things are gonna blow up. I had my Wife all upset.

 

[steve_k]

Right.....

Hey Mark if you want to remove a thread....choose this one dude!

Steve
(Amp Tech / Chief Bottle Washer / Bus Driver)

 

[glip22]

Right.....

Hey Mark if you want to remove a thread....choose this one dude!

Steve
(Amp Tech / Chief Bottle Washer / Bus Driver)

Your SOL. Your not stirring shit. You're just looking like a dumbass. Hey, I tried to shoot you some dumbass bail

 

[steve_k]

Right.....

Hey Mark if you want to remove a thread....choose this one dude!

Steve
(Amp Tech / Chief Bottle Washer / Bus Driver)

Your SOL. Your not stirring shit. You're just looking like a dumbass. Hey, I tried to shoot you some dumbass bail

 

[jerrydyer]

Steve
the compubias is better. plug and play, plate voltage, MA across 1 ohm and actuall wattage per tube. in the display at the same time.

 

[steve_k]

Steve
the compubias is better. plug and play, plate voltage, MA across 1 ohm and actuall wattage per tube. in the display at the same time.

Agreed. Thanks for the heads-up. Just bought one....

Some amps I just check the old fashioned way. Others are just a pain in the ass without a bias probe.

Steve

 

[jerrydyer]

ive had mine for about 4 years. I had one problem. he fixed it asap shipped back asap no charge.

thats customer service so I talk about compubias any chance I get.

 

[LP Freak]

I only see two probes on it. How do you test a quad?