No sound output cable shocks you all the lights and tubes on ...tubes are a red glow , instead of blue,, if you unplug the guitar and touch the cable end you can hear a faint whistle in the amp sounds like its comming from the transformer ,i just got it back from the repair shop it did the same thing last week at a gig . i played about three songs onstage and the sound stopped again just like before what could this be?
SOURCE: PEAVEY ECOUSTIC 112 W/ NO SOUND ----muted?
Please the the amp with PA again then if it plays then and cable is fine you get the guitar circuit as it may have loose circuit you need to get it serviced...
SOURCE: Yamaha CVP 309-When I power it up, red power light comes on, but
You have to remember that the voltages coming out of the power transformer are A.C. and the voltages used by the devices in the keyboard are D.C. Check for voltage rectifier I.C.s between the transformer and the rtest of the circuits. They should look like squares with 3 pins coming out of the bottom of them and metal backs that protrude above the top of the black squares. Use a volt ohm meter on direct current range and clip the black lead to a circuit ground such as a ground on an output jack. Touch each pin one at a time taking note of the voltage. If you find one that has the same voltage on all 3 pins it is probably shorted. I think the voltage should be about 12volts direct current positive or negative depending on the circuit. Each one will have a code that you can cross reference on the net to find the pinouts and specs. The same thing goes for all the I.C.s If you can find the pinouts for any that you suspect look for the power supply pins and check what the voltage is. Some will have two supplies, one negative and the other positive. If you find an I.C. with power at all pins or ones that should have no power only signal then it is likely shorted. Go slowly and don't bridge two pins at once by accident and you might be able to find the problem without the schematic or a service manual. There is a memory battery (CR2032) that power the memory that might be dead but that should only affect the programmed sounds not the LED or the amp chip. Hope this helps. Do not measure A.C. with the D.C. range or you'll burn out your meter. Use safety precautions with a live device.
SOURCE: JCM2000 DSL100 No Sound
Not likely to be a fuse. The bane of electrical amps are the connectors.
Often the speaker and more commonly the input 1/4 inch connectors go bad. Sometimes caused by side loads when cables are yanked or tripped over.
Be careful of running amps IF the speakers are not connected OR have bad connectors or cables. You can arc over the tubes or pop transistors.
Get a cheap Volt-ohmeter from HarborFreight or Radio Shack and test your cables and connectors.
For a tube amp, your should find relatively low resistance at the speaker connector (certainly under 20 ohms). Do this with power off.
SOURCE: My MT-2 wont distort my guitar.
A few things to try....
Usually the adapter will over ride the battery when used.
1) Make sure your 1/4" cables are working properly without the pedal "in-line".
2) Take out battery, and use just the adapter only. Make sure it is the correct and proper adapter that works with Boss. Usually the PSA-120. If you are not using a Boss Adapter, make sure yours is a direct replacement with same specifications. 9V/200mA. And "tip negative". DO NOT use Radio Shack stuff, nothing against them, but there adapters just don't mix well with Boss products and the like.
2) Try just the battery, no AC adapter. Remember to unplug the input when not in use. Saves battery.
Basic rule of thumb...when using correct AC adapters for all your pedals all the time, and all sounds good, then take out the batteries.
If you still experience problems, it would be an internal IC chip most likely. From there post another question maybe.
SOURCE: The amp plays fine for
You say the "tubes are fine" I take it that you have either replaced them with new or used a very sophisticated tester on them. A heater-cathode short might cause the symptom. There are a bunch of tests I would want you to run alnd get back to me with the results.
Heat up the amp but DO NOT play anything into it for the usual failure time or more and they start to play i... did hum occur WITHOUT playing? With all volume controls down does the hum occur?
The right tools is an oscilloscpe to fing out if the filter caps are good. These are C31, C33, C35, C36.
With hum present in failed stater, plug in a grounded plug into the power amp in jack... if hum is stiil there, check the +/- 16 volts regulating Zener for ripple. get schematic here:
http://elektrotanya.com/fender_hot-rod-deluxe_sch.pdf/download.html
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