Vox AVT-40 Headphone socket stuck to on. Fixable easily?

Jetsam1

Hello,

My Vox Valvetronix has decided to keep itself set to headphone mode. Is this likely to be an easy fix as I think it's just the socket that has an issue or am I in trouble? It's about 6 years old or so and was working fine. I know I should really move it on and get a european spec one but it's a decent amp.

I have always been a bit afraid of opening up electronics......! No idea how to find amp repair here in Budapest!!

Danny1969

The headphone jack has switchs which switch out the speaker when a 3.5mm jack is inserted. These joints go bad on the PCB leaving the speaker disconnected as if headphones are in. It's not a hard fix, the input and headphone socket is on it's own little PCB so no need to take the whole amp apart. 

Jetsam1

So I just need to open up the back then and it should be obvious? Would this be a little new solder or can I disconnect the headphone PCB entirely and it will be fine? I must admit to knowing nowt about the insides of amps!

Danny1969

No you can't disconnect it .... it won't work at all if you do. 

You can re do the joints by reflowing them with a good iron and a little solder, if poss suck or braid off the old stuff and then re do but if you don't have braid or a solder sucker just reflowing them will work. Don't use too much heat otherwise your destroy the pads cos the PCB isn't great

On the amps I've had for repair a couple of customers have requested the headphone socket be wired across so the speakers always in circuit which is reliable but obviously means you can't use headphones 

Here's one I did a while ago, yours should look similar 

ecc83

Do get the old solder off if you can and do use braid. I have found suckers to be more likely to damage print and suckers take some "larnin"!

Once de soldered scrape the tags with a sharp model knife blade to get to fresh metal.

This is a common problem with PCB mounted jacks, DINs dah di dah....BTW lead 60/40 is fine and best.

Dave.

Jetsam1

Right. Thank you all! I don't think I have access to the right equipment so I'll go into the city and ask around a guitar shop if they have a tech or know someone who can effect the repair. At least now I know what the problem will be and possible solutions.

Thank you!

Danny1969

If you can't find someone local you can always post the PCB to my workshop and I'll do it.