the Poor Man 660 support thread

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Yesterday night I suddenly realized that the sidechain section can´t be the problem because it is AFTER T4, so I thought it is maybe the second tube section just BEFORE T4. ANd indeed, when swapping the tubes my meters needle stopped to move, everything seems to be fine now  8)
Thanks everybody four your help!
Emre
 
OK High Five everybody.

I have a working PM670.

Analag..... Seriously ........ you have designd a wepon.
This has been my most challanging build so thanks everybody for your support.
Damn it ......... I said I wasn't gonna cry.  :'(







Who want's to buy an Avalon 747 ?
 
Well I got so excited that it's all racked up.

I took some pic's before it was finished and was a little messy but what the heck hey.

P1010056.jpg

P1010054.jpg
 
rrs said:
Well I got so excited that it's all racked up.
I took some pic's before it was finished and was a little messy but what the heck hey.

headbang.gif
headbang.gif
headbang.gif

congratulations, I love the creamy chickenheads. They arrange nicely with the beautiful meters. Enjoy the compressor monster.
regards
Bernd
 
Hello!

Can anyone tell me, if you please, the link regarding the PM660/670 and the Sifam AL20SQ... I know that there's some resistor I need to change...
I'm planning wire a 5K trimmer between the VU leads to regulate the zero...
I power up my PM670 and both VU stuck at the right side... I didn't adjust RV3 and RV6 yet...
Can anyone help?

Cheers,

Eddie ;D
 
rrs said:
klaus2you said:
For those who used sifam AL20SQ like me, substitute R6 22K with a 47ohm or little higher.

This worked for me.


Rrs,

congratulation for your build!!

SaMpLeGoD,

I finaly removed the resistor and solder a 100ohm trim, i first tried a 5k 25turn trimmer and removed it to get something more precise but it works.
Also before you trim your meter precisely to O, power up your unit whith the top of the rack close for a while.

Best, Adrien.
 
Hey rrs and Adrien!
Thanks for the fast reply!

Adrien, did you use the 100Ohm trimmer to set the Odb on the Meter? did you put that trimmer with access in your front panel for future zero resets? or do you simply regulate the unit with the 100Ohm trimmer and set the 5K trimmer (that was supposed to be across the Sifam lugs)to be acessed from the front panel?

Thanks a lot!
I'll put some pics soon ;)

Eddie ;D
 
I use a Sifam AL22 and ended up doing following steps:
1. remove the 22K resistor and replace with a 2K trimmer
2. remove the rectifying bridge and resistors inside the meter
3. put a 50K resistor in series to the meter

Before doing step 2 I couldn´t get the needle to zero.
Before doing step 3 I could get the needle to zero but it was "unstable" moving left and right when moving my hands around it or the wires.  ??? But now it behaves like it should do,well, tracking is not 100% but...
I´m not sure if another value in step 3 would be "better", someone with more knowledge could give the answer...
Good luck, Emre
 
hello everybody,
I am having troubles with my 670 in the power supply section.
can anyone post any static voltage readings (or PM) so I can compare them with mine?
many thanks
 
done.
Q3 was blown.
I kindly recomend to follow silent art suggestion: since I have used 2X IRF840 the supply has exactly the right voltages...


Best,
Mattia.
 
I used IFR820 and IRF840, and so far I have all the voltages with correct values and working... do you think I'll have problems if I don't sawp the IRF820 by the IRF840?

Cheers,

Eddie

 
Hi,
as Mata_haze told, we have solved the problem with the PSU (the PM we are working on is the same unit),
so the voltages are OK without LOAD , but when i plug-in the two boards there is a huge drop:

245V -> 77V
136V ->36V

The heater is perfect at 6,35V

May i suspect the IRF regulators not working properly ?

:mad:PM670 is a complicated beast !) :mad:

Many thanks for your help
 
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