Neve 31102 issue

[fffaustino]

hi Groupdiy, maybe it is a newbie question but i need help with this...


I am the fortunate owner of a pair of Neve 31102s, one is a version 1 with the line mod and the other is a version 2, unmodded.

None of them had installed 4M7 resistors between positions at the high frequency switch, to avoid click noises.

But the fact is that the modded one has loud click noises when selecting frequencies and the unmodded works with no issues at all.

I have soldered the 4M7 resistors in the faulty one, and have installed a brand new switch but no luck at all. B283 and b284 cards have been properly recapped and i was thinking that maybe there´s something wrong with the mod that could have relationship with the issue, don´t know….somebody more Neve experience than me could give me a clue.

Any help really appreciated and sorry for my ignorance..

Alfredo (fffaustino at Groupdiy and Gearslutz)

 

[radardoug]

You say the cards have been properly recapped. Did you have the problem before recapping? Clicking indicates the presence of d.c. on the switch. Thats what you should be looking for.

 

[fffaustino]

hi radardoug and thanks for your answer,

yes, the problem was there since i acquired the module. I tried the 4M7 resistors after recapping the cards and the module electrolytics, but nothing has been fixed. I have no experience looking for D.C....just basic soldering, recapping and so. What should i suppose to do to avoid the D.C. of the switch?  According to the 1084 schematic i have realized that the 31267 has no capacitor at secondary, i have read that this capacitor is for avoiding the ringing but could this have to do with the problem?

thanks

 

[radardoug]

Do you have a multimeter? Meter the switch contacts and see if there is d.c. there. Then pull the cards around that switch and see if the d.c. goes away.

 

[fffaustino]

Thanks again radardoug,

i have done it as best as my limited electronics knowledge has allowed me;

I have metered 4.6 mV at switch contacts and i have pulled cards around it with no results. Maybe that value is something normal,
i don´t know. I have replicated this metering with the other module and surprisingly the value is a bit higher, around 5.8 mV...

The 4.6 mV value has lowered - but not disappear - after pulling the b283 preamp card, but i have not monitored other remarkable changes.

When i got the module, the line input cable shielding was soldered to the E pin (0 V) instead of the V (ground)  pin, as the 1084 scheme indicates. I reversed this situation, it may have been a wrong movement?

Many thanks

 

[radardoug]

Well, if the other module that doesn't click has slightly more voltage, then that is not your problem.  Is this clicking happening with signal going through the channel, or only with no signal through the channel?  Do you have a scope? If not, you are out of your depth, consult a professional! Hehe!

 

[fffaustino]

Clicking happens with signal and without it...today i have recapped the 4 470uf's that are mounted on the frame but no success with the clicking..

Unfortunately i have no scope so maybe i will have to investigate a bit more or send the module to a profesional...

Thank you so much in any case and best regards from Spain!

Alfredo