U47 multi pattern build

[Spencerleehorton]

well ive changed everything apart from the capsule and transformer now!!!
i was suspecting the 7 pin socket on the psu as when i had the pattern disconnected i was still getting 1-2v on that pin?
ive changed the 7 pin socket on the mic, now ive changed the pin from pin 6 as pattern to pin 3 and it gets the same 1-2v disconnected?
very strange?
the design must be right? so ive got a ghost gremlin somewhere?

 

[Spencerleehorton]

changed the capsule now and still the same, changed the lead and still the same?
must be the PSU then?

 

[Spencerleehorton]

I think I may have found my problem!!
Watch this space, going to change a few bits then test again!!
Fingers crossed!!

 

[rock soderstrom]

I think I may have found my problem!!
Watch this space, going to change a few bits then test again!!
Fingers crossed!!

I'm curious what the problem is, hopefully you can solve it.

 

[Spencerleehorton]

alas not what i thought, as it a voltage problem i thought maybe it was a low voltage capacitor on b+ part of PSU, ive changed and checked the caps and PSU and all is correct, getting good 120v and 5.5v on heater, still this delay and rise in voltage where the mic cuts out for 30 seconds and the capsules are back to front?
i honestly cant think of what i havent changed now!!!

 

[Spencerleehorton]

Could we go over and make sure I have made the correct gnd connections please?

IEC to chassis as close to iec as possible
Psu gnd to 7 pin socket chassis
H- gnd to separate gnd and separate pin on 7 pin connector or connected to same gnd at mic which will then gnd at 7 pin chassis gnd on psu?
Selector switch gnd?
Xlr 3 pin chassis and pin 1 to chassis and connected to 7 pin chasssis gnd?

This would really help as I’m sure I’ve wired it wrong?

 

[pasarski]

I don't think grounding per se could cause the symptoms. I would suspect some cap is connected in wrong node. Can you post a picture of back of your board?

 

[Spencerleehorton]

I’m going to rebuild the mic again and will then post some pictures of everything.

 

[RuudNL]

About the delay after switching patterns:
Do you still have 10000 pF between the membrane connections of the capsule?
Reduce the value of the capacitor to 1000pF (or maybe even 470 pF) and see what happens...

 

[Spencerleehorton]

ive just tested another PSU but just on cardioid and it sounds perfect, lots of level, the capsules are the right way round, so i actually suspect the original mains transformer is bad, i will replace it to test with another and see if i can repeat this working psu with the mic, then start to add back the pattern switch.

before with the other PSU the mic wasnt getting much volume out and was noisy and patterns even with just cardioid sounded wrong, some progress at least!!!!

 

[Spencerleehorton]

I have finally got this mic working correctly and can confirm all patterns work!! finally
the problem seemed to be someof the turrets where not connecting at the rear of the pcb, so i think in future i'lll use eyelets.
so sorry about the fiasco!!!

 

[SIXTYNINER]

I’m going to rebuild the mic again and will then post some pictures of everything.

Only as well,
possible some about ?
cheers

 

[Spencerleehorton]

yeah i will post some, just gotta few days of work to do first!!