3U Warbler IV issues

[mattrico]

Hi all, I recently bought a 3U Warbler IV and it was having issues from the get go (the guy I bought it off didn't admit it had issues, so lucky me I get to try and fix it!).
Anyway, there are 2 main problems I've noticed:
1. The V switch does nothing. Flicking between the 3 voices, even waiting a while, seems to have zero effect on the sound.
2. It slowly loses gain over time. So when I plug it in, it has strong gain, but over time you can see it losing gain until it hits a point that it doesn't drop anymore. I think this is also related to the pad switch, which seems to behave sometimes and not others.
Short of ripping the capsule and transformer out to use in another project mic, what can I do? If it's too much mucking around to fix it, I think I will just get the capsule and transformer and buy another apex 460 style mic to drop them into, which is much more within my means than the real technical stuff that might be required to fix this.
Any help is appreciated!

 

[pucho812]

have you contacted 3U about it?

 

[micolas]

Hi all, I recently bought a 3U Warbler IV and it was having issues from the get go (the guy I bought it off didn't admit it had issues, so lucky me I get to try and fix it!).
Anyway, there are 2 main problems I've noticed:
1. The V switch does nothing. Flicking between the 3 voices, even waiting a while, seems to have zero effect on the sound.
2. It slowly loses gain over time. So when I plug it in, it has strong gain, but over time you can see it losing gain until it hits a point that it doesn't drop anymore. I think this is also related to the pad switch, which seems to behave sometimes and not others.
Short of ripping the capsule and transformer out to use in another project mic, what can I do? If it's too much mucking around to fix it, I think I will just get the capsule and transformer and buy another apex 460 style mic to drop them into, which is much more within my means than the real technical stuff that might be required to fix this.
Any help is appreciated!

Has anyone made any changes, interventions in the microphone?
Was it defective and did he partially repair it?

 

[mattrico]

have you contacted 3U about it?

Not as yet. I didn't think Guosheng would be too interested in a faulty used mic, even though I have bought a couple of capsules off him in the past. But I guess it's probably worth a shot!

 

[mattrico]

Has anyone made any changes, interventions in the microphone?
Was it defective and did he partially repair it?

Not that I can see. Everything looks stock.
The guy I bought it off didn't do anything to it by the looks of things. And if he did, he didn't admit anything to me when I told him that it wasn't working properly.

 

[micolas]

Not that I can see. Everything looks stock.
The guy I bought it off didn't do anything to it by the looks of things. And if he did, he didn't admit anything to me when I told him that it wasn't working properly.

Then it's worth trying to fix it

 

[mattrico]

Then it's worth trying to fix it

Yeah it was too long ago now (late last year). I don't think the guy would care. Best to fix it myself and reach out to Guosheng to find out his thoughts.

 

[micolas]

Yeah it was too long ago now (late last year). I don't think the guy would care. Best to fix it myself and reach out to Guosheng to find out his thoughts.

I was referring to the possibility of repairing it yourself.
I would start with cleaning the high-impedance entrance area with isopropyl alcohol, very carefully.
Then with testing the capsule in another circuit, or testing another functional capsule (of any type) in the Warbler.
Check switches
Then measuring the voltages at the relevant points, the BIAS of the jFET, checking the DC/DC converter, check, replace coupling or filtering capacitors
etc., etc.
Possible causes of incorrect operation must be methodically checked and eliminated one by one.

 

[Voyager10]

Can you post pictures of the insides, especially the circuit boards?