the Poor Man 660 support thread

[dagoose]

I probably overlook it but what should be done with the elco's between the PSU connector on the pm660 compressor board??? so the ones that are on both sides of the connector.
There is no value given and nothing in the BOM and on the silkscreen.
Are they optional? i think they are part to the high voltage section.

 

[skal1]

hi thanks moby,

i have a bypass ? , i have wired the bypass boards up and they are not working correctly .I have connected the - to the bypass pcbs and + to the switches  and from the switches to the corresponding relay boards is this correct,, the reason i am ask is that when both switches are in bypass it works ok but if i switch one of the switches to on and try to switch either of them on at the same time only one seems to be working properly .

regards

skal1

 

[RAM]

I have connected the - to the bypass pcbs and + to the switches  and from the switches to the corresponding relay boards is this correct,

The bypass boards don't take the - voltage. Just send the +12V from the PSU660 board to the relay. But make it switchable (no 12V sent to the relay board gives bypass).

I probably overlook it but what should be done with the elco's between the PSU connector on the pm660 compressor board??? so the ones that are on both sides of the connector.

I presume you mean the space for the electrolytics on the pm660 boards? They are completely optional. No need to use them if you don't want.

Rob

 

[skal1]

The bypass boards don't take the - voltage. Just send the +12V from the PSU660 board to the relay. But make it switchable (no 12V sent to the relay board gives bypass).





Rob

so why is their to wires leading to the relay boards on the wiring diagram

skal1

 

[RAM]

One is +12V and the other is a connection to ground. Bear in mind the wiring diagram doesn't show a switch for to turn bypass on and off. It is a little bit confusing due to the colours Volker used for the description just beneath the connection on the diagam.

Rob

 

[Moby]

the reason i am ask is that when both switches are in bypass it works ok but if i switch one of the switches to on and try to switch either of them on at the same time only one seems to be working properly .

So you solved the gain issue? This is the another Q? Did you measured voltage on relays when you switch bypass. Any drop from 12V?

 

[skal1]

yes can of solved just turn down the source level right, no i have not measures for any voltage drop but i will try that next , is it the way i have wired the relays?


skal1

 

[Moby]

If you have voltage drop (12V) when you turn bypass on than it's possible that you have a +12V psu problem of relay is faulty. Probably the 1. one is possible  ;D

 

[Grooveteer]

I probably overlook it but what should be done with the elco's between the PSU connector on the pm660 compressor board??? so the ones that are on both sides of the connector.
There is no value given and nothing in the BOM and on the silkscreen.
Are they optional? i think they are part to the high voltage section.

They're not needed as per Volker 

 

[skal1]

just to ease my confusion of bypass relay boards, 0v goes to one pin on board and then you cut postive rail and insert swicth then from switcth to bypass board ,am i correct in thinking this ?



skal1

 

[Moby]

yes

 

[skal1]

sorted thanks for everybodys help ;D


skal 1

 

[dagoose]

I probably overlook it but what should be done with the elco's between the PSU connector on the pm660 compressor board??? so the ones that are on both sides of the connector.
There is no value given and nothing in the BOM and on the silkscreen.
Are they optional? i think they are part to the high voltage section.

They're not needed as per Volker 

OK, i allready thought so but now i'm sure
I wanted to know for sure before i all wired it up and then came to the conclussion that i needed it anyway and have to remove the boards again.

 

[dagoose]

Ok.. some progess..

One channel is 80% wired up and frontpanel and stepped switches are done and mostly wired.
Second channel has to wait a bit longer since i have 2 DOA edcors

The PSU is working.. well... not 100%.. i have a weird problem with the + and -17v, i have + and - 20v (approx) and whatever i do with the trimmers, the voltages stay the same. ???
I have tried a load of 500r to see if it needs a load but it's just giving these voltages and that's it.
What can go wrong here?

 

[[silent:arts]]

the +/- 17V PSU is regulated, they don't need a load.
without mains power use the trim potentiometers, to one end, to the other end.
set them in the middle and try again with power.

 

[lolo-m]

Ok.. some progess..

One channel is 80% wired up and frontpanel and stepped switches are done and mostly wired.
Second channel has to wait a bit longer since i have 2 DOA edcors

The PSU is working.. well... not 100%.. i have a weird problem with the + and -17v, i have + and - 20v (approx) and whatever i do with the trimmers, the voltages stay the same. ???
I have tried a load of 500r to see if it needs a load but it's just giving these voltages and that's it.
What can go wrong here?

Don't forget to look at the wiring guide to turn the good trimmer when testing, they're oposite order than output... I make the mistake at every change I do  ;D ;D ;D

 

[dagoose]

Ok.. some progess..

One channel is 80% wired up and frontpanel and stepped switches are done and mostly wired.
Second channel has to wait a bit longer since i have 2 DOA edcors

The PSU is working.. well... not 100%.. i have a weird problem with the + and -17v, i have + and - 20v (approx) and whatever i do with the trimmers, the voltages stay the same. ???
I have tried a load of 500r to see if it needs a load but it's just giving these voltages and that's it.
What can go wrong here?

Don't forget to look at the wiring guide to turn the good trimmer when testing, they're oposite order than output... I make the mistake at every change I do  ;D ;D ;D

ahum... please don't call me stupid.  :-[
-17 and 12v sharp now.  8)
One channel even came alive now, at least it's giving sound and compression, only thing i have to do is set the trimmers and add a potmeter to the meter, it's pegging in the corner now.
But at least it's allready working!  ;D

 

[lolo-m]

ahum... please don't call me stupid.  :-[

If I call you stupid, I must call myself stupid as I spent some time with this !!!
Refer my note to self !!!

 

[dagoose]

ahum... please don't call me stupid.  :-[

If I call you stupid, I must call myself stupid as I spent some time with this !!!
Refer my note to self !!!

;D

 

[inputoutput]

hey guys, I´m one of three independent poorman-builders striving with the exact same problem. We are all sitting around waiting for someone to enlighten us here at the forum, so that we can fire up our builds. We are hopefully very close…

The voltages from the 245V and 136V drops fast -when one or several tubes are inserted. The same thing happens with only one audio-pcb connected.

Similar problems have been mentioned earlier in this thread, but no solution has been presented as far as I can see.

When powering up the PM670 with all tubes inserted, the unit works and sounds good for a few seconds, (Meters work too), before the voltages dive from 245V (and 136V) to below 50V. (Heatervoltages 6.3V and -17V stays constant.) 

The audio-pcbs have been searched up and down for shorts, but I can’t find any.  And the PSU gives correct voltages with no load.

I have two IRF840A at Q4 and Q5.  I see little difference on the spec-sheets between IRF840A and IRF840B. So I guess 840A are ok?

So, IF there actually are no shorts on my PCB. Could the voltage drop be caused by the edcors´?  Could there be something wrong with Bernbrues group-buy power-tranny? Nah...  What can it be?  where does my voltages go?  Any hints would be greatly appreciated.