Sinclair ZX80 / ZX81 / Z88 Forums

gozzo wrote:i assume the power supply you are using is ok and up to at least 8v,..and correct polarity?

Yes it is worth checking that hte Spectrum works at least - press a key after turning it on and hold it down - you should hear clicking as the Spectrum repeats the key.....

Yes, I heard clicking, The problem is my video feed, how do I fix that?

Thanks for the power check, and most of all thanks for actually listening to me.

Are you having problems with both of your Spectrums, or just one of them?

Do you have more than one TV to try? Some TVs work okay, others will just ignore the video signal from the Spectrum.
What type of TV(s) (LCD / CRT) and make and model, have you tried?

On the computers you are having problems, can you please post a picture of the area of the Spectrum's printed circuit board where the modulator is (the modulator is the silver metal box that has the RF/UHF TV output socket on it). A top view and also a view of the side that has the wires to it.

Do you have, or have access to a digital multimeter?

Mark

and open the lid of the modulator and post a pic of its innards...

My TV is a Technika 22'' LCD TV. Product Code TX22D14BTCDG963

EDIT: I having a problem on both of them.


Thanks for the help.

Hi all.

By "Model 2", I think he is referring to the 48k+ (Plastic Keys)

Hi "ZX82".

I would Plug the Power Supply into the Spectrum, and Turn on the Power Supply.

Pick the Computer Up, and Listen to the Speaker Underneath, If you hear a Constant BUZZ, she is Powered ON !

Next, connect your RF Out to AV1 or AV2 on your Modern TV, Select AV1 or AV2 with your TV Remote. If you get a Picture, she has been AV MOD'ed.

No Picture, you may need to Tune on your TV, using Standard Old RF methods, and use a Good RF Lead from Commodore 64, SEGA MEGADRIVE 1, ATARI 2600, all will Work. Try a few, as yours could be CACTUS!

If you still get Nothing, could be DEAD or Dying Zeddy!

Darren in OZ