Bush TR82C.

[Robert Darwent]

have cleaned contacts & when switched on a buzzing constantly from speaker & a very faint staion when tuning hardly any volume even when turned up full

Well, at least you're getting a station now.

It sounds as though the waveband switches, volume and tone pots need a good clean (which is to be expected) with a switch cleaner like Servisol 10.

If you haven't got any, rotate the volume and tone controls quite vigourously several times to see if that improves the situation any.

Can I ask how much experience you've got Laurie with radios and electronics? Can you follow a circuit diagram and have you any test gear like a multimeter?

Reason I'm asking is that I don't want to confuse/lose you with some of the things I might say or ask you to do if you're a complete beginner.

Regards

[Refugee]

Wonderful.
Does it have those capacitors that are red and black with the value written on yellow sticky tape?
The two sets I have came from the same trader and both had been dropped and the chassis was loose also on both.
One had the chassis propped up with a newspaper that was only about 2 years old. On both the switches were clean as they had been kept in use.
Do indeed try it on both wavebands every time you test it as this will help you to clean the switches up.
You will need a soldering iron and if you are not used to using one seek out a bit of scrap and spend an evening removing the components without damaging them or others near by. An old flat screen or computer will do for this.

[lol30]

have cleaned contacts & when switched on a buzzing constantly from speaker & a very faint staion when tuning hardly any volume even when turned up full

Well, at least you're getting a station now.

It sounds as though the waveband switches, volume and tone pots need a good clean (which is to be expected) with a switch cleaner like Servisol 10.

If you haven't got any, rotate the volume and tone controls quite vigourously several times to see if that improves the situation any.

Can I ask how much experience you've got Laurie with radios and electronics? Can you follow a circuit diagram and have you any test gear like a multimeter?

Reason I'm asking is that I don't want to confuse/lose you with some of the things I might say or ask you to do if you're a complete beginner.

Regards

i can read a basic circuit diagram & i have a digital multimeter & can check voltages & trace current flow,& i know most of the components in a radio but i am a beginner
thanks laurie

[lol30]

Wonderful.
Does it have those capacitors that are red and black with the value written on yellow sticky tape?
The two sets I have came from the same trader and both had been dropped and the chassis was loose also on both.
One had the chassis propped up with a newspaper that was only about 2 years old. On both the switches were clean as they had been kept in use.
Do indeed try it on both wavebands every time you test it as this will help you to clean the switches up.
You will need a soldering iron and if you are not used to using one seek out a bit of scrap and spend an evening removing the components without damaging them or others near by. An old flat screen or computer will do for this.

yes it does have those capacitors & can solder ok
thanks laurie

[Refugee]

Well the transistor voltages are easy to do on the TR82 as they are on the top of the chassis. they read from left to right from the chassis side. The diagram is marked 1 emitter (yellow) 2 base (green) and 3 collector (blue) plus a spot on the transistor body..
Post up the readings and we can give you a list of parts to check.

[lol30]

hi & thanks
i hope these readings make sense
t1 /oc44 /7.07/1.06/1.06
t2/oc45/0.14/0.31/7.62
t3/oc45/0.51/0.68/7.37
t4/oc71/1.15/1.29/1.63
t5/oc72/1.63/1.45/8.85
t6/oc72/0.01/0.16/9.42
t7/oc72/9.42/0.16/0.01

[pwdrive]

Sought of, normally you would head the columns up E. B. C. and record the voltages on the respective transistor lead outs ie: the actual Emitter, Base, Collector.
Makes diagnosis a bit easier.
The one that jumps out in the table is the OC44 base voltage, but it would depend on what type of meter you are recording the voltage with.

Lawrence.

[lol30]

hi & thanks
yes i realise now i should have marked them up,i used a laser digital multimeter

[pwdrive]

No worries, the OC44 is the self oscillating mixer (Frequency Changer) sometimes measuring the voltages on a device employed in that type of stage can be misleading due to the oscillator. If you look at the manual the DC voltage check for the emitter of that stage is taken from the signal ground end of the emitter osc coil and not from from the emitter itself.
Have you managed to pick up any stations better since you started?
Robert mentioned earlier about the switch contacts, always a good start, nothing worse than a lesser fault masking a primary fault if there is one.
If you can tune in a station then this would imply that the Osc/Mixer is working though not necessary up to spec if there is a gain fault in that stage.

Lawrence.

[lol30]

hi i will check that
unfortunatly the station has dissapeared again now but i still get a hiss & crackle from the speaker when turned on which is loud at first then goes really quiet quickly
all contacts have been cleaned
regards laurie