Tip & How-To about Music

A) basically it has to be acted upon by a supply voltage of at least 95V to work. sample picture

A) basically it has to be acted upon by a supply voltage of at least 95V

to work.

sample picture

b) of course, assuming the horizontal deflection oscillator works, same

with the horizontal drive and horizontal output transistor

it would generate output voltages on the secondary terminals

and 200V line will be active sending voltages to the

Video Drive circuits. Of course high voltage will be generated

ranging to at least 30 KV and there will be voltages on the G2 of the tube.

c) the easiest test point to look when it is oscillating, is the CRT heater

voltage, the heater lit when flyback is good ( mostly at night times when it

is dark ) and you can hear sounds, too.

here is a sample image

marked with letter H and H1

Green Arrow for the G2 voltage

d) having a B+ voltage reading of 75 V or lesser ( primary pins )

indicates a bad or partially shorted flyback, assuming your

horizontal output transistor and power supply are good & OK.

sample of H out

These only applies to CRT type TV's.

Posted by on

Music Logo

Related Topics:

Related Questions:

1 Answer

Will a tascam m1600 function correctly without a specific power supply?

As long as your power supply is supplying the correct voltage and the amp rating is sufficent, and of course the power supply itself is functioning, then your problem is more likely to be a routing error somewhere.. it's probavbly best to center all controls, disengage all switches, and start over from nothing. You should also check that what ever you are using to hear the signal is functioning correctly as well.

Dec 28, 2015 | Roland Music

1 Answer

Mixer Switch on and after a short period theres a noise that sound like a machinegun and a Hiss sound through the speakers

I assume that the power-amp is good.
This noise, of course due to defective parts inside.
But, which section is it? Chances are:
  • Amplifier circuit in the Main-Outputs. If the MAIN MIX in the minimum position and still noisy, then the damage in that section.
  • At one or several channels. Let's test.
    Set to minimum volume for all channels and MAIN MIX. EQ=flat. FX=minimum. TRIM at half (let's try at 12 o'clock).
    Raise the MAIN MIX, let's say at 15.
    Gently, raise channel 1 volume to maximum, listen, if there is no noise, channel 1 is safe. Lower the volume to the minimum again. Move to another channel in the same way.
    If found noise, that is where the problem is.
Actually, many more detailed steps for testing, but the description is too long. This above is a simple way.
Circuit power supply should also be checked, whether all normal voltage.



It is part of the image of the amplifier section circuit.
Parts which may be broken is the IC 64,65,77.

Sep 13, 2015 | Behringer XENYX 2442FX Mixer

2 Answers

How do u check pcb board on musical equipment and on other equipment the only tool i have to check is a Fluke Multimeter but is there any other stuff that is need to inspect and Diag. these boards ple

One of the first things a technician does with a voltmeter it to check 'all the voltages' in a system are correct..

Even without a specific circuit diagram for the board, 'Applications Notes' for chips and seminconductors will give nominal expected voltages in a working circuit.

Remember you can burn out the meter by connecting it to any source of current when on the Ampere or Ohm settings.
Technicians usially start at a high (highest) Voltage range setting and work downwards..

Providing the maximum Voltage is not exceeded on any range, whether it is AC or DC will not damage the meter.

'Fluke' by the way are a 'top end' professional product - check the price ;)

Nov 25, 2014 | Gemini Sound Products Music

1 Answer


The guitar was made fairly recently - after 2012 probably. Like the number indicates, it's US-made. Fender does not currently offer Tele's with copper colored aluminum pickguards, so that might be an aftermarket addition, assuming, of course, the picture is actually the guitar you have.

Jul 13, 2014 | Fender American Deluxe Telecaster

1 Answer

What is wrong with it?

FIlter capacitors in the positive supply are likely failing. These will be the larger metal cans- one may be bulging. Either way, one of them is shorting out after a certain voltage potential is achieved and causing your problem.

Replace the caps in both the positive and negative power supply sections and this should alleviate the issue. Match the working voltage rating, or even one step up in working voltage. yours are likely rated 25 volts, so a step to 35 volts would not pose an issue.

Apr 06, 2012 | Behringer MX9000 EURODESK 24 Channel In...

Not finding what you are looking for?

4,636 people viewed this tip

Ask a Question

Usually answered in minutes!

Top Music Experts

Michial Gueffroy

Level 3 Expert

1138 Answers


Level 3 Expert

79865 Answers

Brad Brown

Level 3 Expert

17167 Answers

Are you a Music Expert? Answer questions, earn points and help others

Answer questions