Fender Hot Ros Deluxe -clean channel not working

[g1]

V1 & V2 must be working or drive would not sound ok. But it could be missing some voltage, so check all items mentioned by 52 Bill above.
Otherwise, there are not a lot of things that are only in the clean channel. Relay K2A could possibly cause your problem, you could jumper pin 4 to 6 as a check.

[Lastnote]

Well fellows that a mouth full of thing to check, but check them I will. Thank you for lending a hand, your are the guiding light through the dark forest!

LastNote

[Lastnote]

Clean channel not work/other problems static surface noise from power section

Well fellows that a mouth full of thing to check, but check them I will. Thank you for lending a hand, your are the guiding light through the dark forest!

LastNote

Fender Hot Rod
Guys, the power section is introducing static/surf noise to the speakers. I pulled all the pre-amp tubes(noise the same), pulled pwr tubes one at a time noise still there, I put new pwr tubes no change. checked all traces,all resistors, caps, re-solder all solder points no change. new output transformer (no change), new pwr transformer (no change). All filter caps are new, the only item I have not change is the choke. Any ideas?

[g1]

So with PI tube removed, the static is still there? Then with it still removed, and running only one power tube at a time, the noise is still there?
When you changed the filter caps, you also changed the bias filter caps ?

[Lastnote]

Hi G1,

yes, yes, and yes; I changed C31/C33/C35/C36.. I am wondering if I have a bad new filter cap or can the choke introduce noise?

Thank you for responding.

LastNote

[g1]

For test purposes you can just disconnect the choke and bypass it with a jumper wire.
Also, you might want to disconnect the protection diodes that are connected to the OT.

[Lastnote]

G!,

I purchase a replacement choke and i installed it, no change. As part of my troubling shooting this last go-a-round of the pwr ckt I replaced the protection diodes (CR4 & CR5), resistosr check all traces, and re-solder all solder points, check ea pin and traced them out to insure no shorts or open ckt. That is way I am thinking I have a bad filter cap although I replaced them tpo. All suggestions welcomed.

Thank you for responding,

LastNote

[km6xz]

My first suggestion is to STOP! Do not replace any more parts until you can prove it is bad. All the problems in the two amps you were writing about were simple that got complicated and worse with replacing parts randomly. Diagnose the problem by: define defect, gather data and come up with an hypothesis that explains all the symptoms. If it doesn't the hypothesis is wrong, start over.
Every time you replace a part needlessly, you make isolating the problem more difficult because you add more potential faults that can camouflage the original symptoms. Now you have a lot more potential defects to consider with all the extra solder joints, new untested components, damage to PC board from desoldering, miswiring. What you are doing is called "shotgunning" and is a very poor habit to get into, it wastes time but more importantly it lowers the value of the unit and makes an accurate diagnosis more difficult. If these are customer units, it would not be ethical to charge for any of the parts you added for no reason. On these consumer/hobbyist forums the assumption that factory solder joints are suspect ignores the fact that any factory solder joint has a much higher probability of being good than any random hobbyist's joints. Sure, there COULD be a bad joint but a properly conducted diagnosis would pinpoint where it must be and does not involved random redoing portions of a unit.
Take and log measurements, and isolate the conditions present when the defect is observed. Those two keys to diagnosis do not involve any invasive surgery on the amp. Make any measurement only after mentally predicting what is should be. If the measurement value is not as you predicted, either it is a clue of importance or it means you do not fully understand the circuit and its operation. Find out why it or your assumptions are wrong. To reduce the temptation to replace parts needlessly, turn off the soldering iron until you have your diagnosis that explains all the symptoms and measurements encountered. If in doubt of how the circuit works, ask or do some research into fundamental electronics. Avoid all sites and forums that tell you what is wrong without knowing all the data you measured, we see that all the time. For example; "my amp has a a buzz[distortion, hum, low gain, etc]" and the advice is "replace all the capacitors because they are old". Amateurs see one defect and assume all other similar sounding reported symptoms have the same cause. Ask a pro who has worked on 2,000 of the same model and they will hesitate to prescribe any specific course of action until a lot more is known about measured values and details of operating conditions, because they have seen 1400 different causes for those 2000 repair complaints. Basic electronics books will be more reliable than internet forums and go you more good in the long run.
But first, stop replacing good parts.

[Lastnote]

To km6xz,
Your comments are condescending and disrespectful towards all the other members who have been helping along. In fact, you are saying that all the advice they have given me on this forum, is dribble and not worth spit! I am 65 year Ret. Army and have had receive intensive training in trouble shooting to isolate communication equipment problems. Just because the manner we have been trying to solve the problem does not subscribe to your methods of working out the problem does not mean it is not another worthwhile method.
It is quite common to substitute a suspected component with a known good one.
You also make assumptions:
• that parts are not test (wrong) new parts and are tested prior to installing. I have excellent soldering equipment (HAKKO FX-888D) more than adequate,
Fluke 87 Multi-meter, and Maxi-Matcher II power tube tester and Maxi-Preamp tube tester.
• Not being ethical, parts that do not solve the problem are not charged (that is my cost), also time spent on solving this problem is “on me” not the customer
(no charge for time spent on problem).
• No reason for changing parts (to eliminate a component when all test are not conclusive), your opinion and everyone has one and it don’t make them right.

So I ask you, where was you at the begging of this process to add constructive advice? You are jumping in, not to add advise how to figure out how to solve the problem in the power section but, to give a lecture to myself and the other members. Lectures are not welcome needed or wanted! Your comments did not help at all.
If you truly want to contribute to my request, here what I have: Fender Hot Rod Deluxe with static/bacon frying and noise surges, all pre-amp tubes are removed, no guitar plugged.

LastNote

[km6xz]

Any experienced tech will attempt to not introduce more variables that confuse the diagnosis, unlike how you have approached this repair. The advice is not condescending, it is a reality of effective diagnosis and what a professional, in any field, is expected to do.

It is one thing for a hobbyist to tinker and experiment with his own gear but to ad hoc shot gun without understanding the circuit is quite another when a trusting customer brings to the "professional" who starts swapping parts randomly and hoping for a fix.

The types of parts you replaced suggested that you were not paying attention to the prior measurements. Every time a part is removed and another the board is damaged regardless of your tool, so yes, the unit value decreases with each misstep.
A lot of techs do try to help and I am one of them but when someone is over his head and charging a customer I pull back, it was his responsibility to know the circuit and basic trouble shooting before taking on the trust task of taking care of other people's equipment.

The haphazard way you approached it is what prompted the strong suggestion to stop and regroup. You do not have to accept it but it does not make it invalid. The suggestion was made to beginners might learn something that would be of value to them later on. If shotgunning was the method you were taught I would be very surprised , but it might explain the very low levels of readiness of equipment in so many units in the military. You bypassed the first premise, that the tech understand the circuit or go off and study it before operating on it. Defending shotgunning is further surprise for component level diagnosis. I hope the next tech he takes it to understands it better.