Metropoulos Forum

Noob question... Just finished my build (100 watt), powered it on, nothing blew (that's good), got conclusive readings on pin 2 and 7 of v4-7 and pin 4- and 9 of v1-3. That measurement was in AC.

Then, following the guide, I checked pin 5 of V4-7 and got ok readings (in the range the guide says it should be), that measurement was done in DC.

Then, I know I should check the voltages against the chart voltage. My problem is that I know that pins 2 and 7 of power tubes should be in AC and pin 5 in DC, but for the rest, like pin 4, should I be AC or DC ? Was it somewhere in the guide but I'm too tired too see ?

Also, I wanted to drain the caps as per the guide, but wanted to make sure I had current in the caps before trying to drain them, and when I checked on the caps itself, using DC on a 600V range,I never saw any readings... how could this be ? Afterwards I did the draining procedure jsut in case. Could someone have readings like I had(pin 2 and 7 of power tubes and bias readings and so on) with such a major problem as having no power in the filter caps ? Is my multimeter good for the dump ?

Was reading the master volume guide to look at the clearer picture in them to help me spot a problem on my 100W and it seems that in the testing sequence, after testing what I tested (bias and heather wires) I shound throw the standby switch (which seems pretty darn logical), but since I followed the guide so precisely I haven't done this (reread it and never saw any mention of throwing the standby switch in the testing sequence).

I'm preparing to work now, but could this explain the problems I got ?

Also, in this master volume guide, I checked the chart and it indicates where AC should be read!

I'll test it this evening... the day will be long.

Let me know if you think I got it wrong...

Hmmm... no one ?

Yes, flip the standby switch when reading the voltages on the pins. Otherwise, there's no high-voltage running through the amp.

Thanks!

That's what I decided to do after reading the other guide. The amp is alive, sound INCREDIBLE and with less bacground noise that my Marshall 1987 RI... Nice glassy sound. Gonna crank it a bit tomorrow!

Thanks for the help. Is it me or the part when we should flick the standby switch is not in the guide ?

Yeah, the instructions leave a few things out.

Do you need to have speakers hooked up when you throw the standby switch?

yes you must have speakers connected when you turn the amp off from standby into high voltage mode. YOu can destroy your amp like that. I made a mistake of pulling the wire out and even one sec is too long.

Invocator wrote:Do you need to have speakers hooked up when you throw the standby switch?

Only if the power tubes are installed.