Fender Bronco Amp - tremolo ticking sound

[Amie]

If the ticking is being created within the Amplifier circuit it should be traceable with a scope? It's usually something discharging. Neon indicator lamps will sometimes cause noise?

Don't rule out external influences, my Watkins picks up a slow clicking noise from my bedroom light, when the light is off. I think that its a capacitor charging through the mains wiring to the switch then making the click as it discharges.

Can you post an mp3 of the noise?

[Bushbaby]

Many thanks Amie
When I get a mo I will see if I can send you an mp3 of the noise albeit it might be a bit difficult to do directly through the forum due to the size of data that can be posted.

One thing I have noticed is that my 11 year old Fender Telecaster Thinline 72 reissue is not earthing as well as it should so that isnt helping with any background noise either.

Best Regards

[Amie]

If the noise is regular and obtrusive then an MP3 at 64 kbps for a few seconds would do fine. Is the noise there when the amp is idle, did you say? Give the scope idea a try, see what the noise looks like and trace the stages back and check the PS too. (Take care with over volting the input of your scope, and check the mains isolation on the transformer as well!)

GL!
Amie

[Bushbaby]

Hi all
This tremolo ticking sound appears to have departed (??). What I have noticed today is like a window scraping sound rather than crackly (dirty connection somewhere?) with the volume at zero and nothing connected. What do you think?

Best Regards

Rob

[Diabolical Artificer]

As the long departed Amie said it's a job for your scope. Go through the scope from front end to OP stage, start at V1a anode, finish at the OP. Try no input first, volume 1/4 say, then crank the volume up if you don't see anything. Set scope IP to AC, vertical amp on the lowest setting, TB to 10nS say.

Another quick way is to pull valves whilst it's on, but not the OP valve, that might be a bit scary for you though. The idea is you pull each valve in turn till the sound goes away, this narrows down your area of search.

Unusual noises are usually cracked resistors, leaky caps, leaky circuit boards, dirty valve bases, dry joints, bad grounds etc etc, but it could be anything hence the need to narrow your focus

Andy.

[Murphyv310]

Agree with Andy.
A scope is your best tool, many are either frightened to use them or cannot interpret what they see. Read up and practice.