Hi, and another orange Indesit...

[mnemonix]

Hi folks

I just picked up an orange Indesit portable for a tenner which I'm rather pleased with. The good news is it seems to work with no major issues except the volume control is so crackly & noisy as to be unusable. I'm hoping either contact cleaner spray or at worst a new pot will rectify this?

It's a bit grubby too and I wondered what advice you might have for cleaning the plastic cabinet without either dissolving it with an inappropriate solvent or scratching the hell out of it with a green scourer?

I hope to run it from a freeview box, but I haven't managed to tune it in yet... am I missing anything obvious here?

Finally, does anyone have a manual in pdf format, or at least could tell me what the push button on the right does? It sort of does something to the sound and signal when I press it, but nothing so specific that I could say quite what!

Thanks for any help you can give me on this,

Chris.

[Steve_P]

Try good ol' soap and water, see what that does. Usually that's all you need.

Contact cleaner should do for the volume control. Spray into the control and work it about.

What Freeview box are you using? Are you sure it is one with an RF Modulator. Some don't, although the sockets are there. Try it with a video and a tape.

I haven't got the Newness book to hand (broken leg) but I wonder if that button is for VHF?

Cheers,

Steve P.

[AidanLunn]

Originally Posted by mnemonix

The good news is it seems to work with no major issues except the volume control is so crackly & noisy as to be unusable.

This doesn't mean that the TV won't display problems in the near future though. The TV may not have been powered up for some time and so some electrolytics on some boards may need replacing soon, as they have lain dormant with no electric charge through them, probably for a number of years. This has happened to me on a Grundig Series S 815 A2105 CUC95 colour portable from around 1982/83 (I can never understand the model numbering scheme Grundig had, hence I can't remember which of these codes is the model number). It worked for a few days absolutely fine and then started having problems starting up from cold - some caps needed replacing in the PSU.

Originally Posted by Steve_P

I haven't got the Newness book to hand (broken leg) but I wonder if that button is for VHF?

I would think that it probably is. Most UK-intended 625-line B&W sets I've seen from the 70s - and some more recent (as well as some early colour sets, albeit for different reasons) have a 405 VHF tuner as well as a UHF one (for those who lived in areas where 625-lines hadn't begun broadcasting or for those parts of the country where the old system of BBC-2 on UHF and BBC-1 and ITV only available on VHF was still carried on).

Now I think the reason why all TVs that have VHF and UHF since around 1980 is only to enable them to be used in another country that is still using VHF, such as the Grundig of mine mentioned above.

Anyway, I've seen loads of these orange Indesit TVs on eBay, and think that they do look like the archetypal "60s TV". Doesn't mean I don't like them though

[AndiiT]

Hi,
From, memory I think that your "mystery" button is nothing more than a simple 'Top cut' Tone control

Regards
Andrew

[mnemonix]

Originally Posted by AndiiT

Hi,
From, memory I think that your "mystery" button is nothing more than a simple 'Top cut' Tone control

Regards
Andrew

Ah, this makes most sense given the rather indeterminate result of pressing it.

Cheers!

[AidanLunn]

If that is the case, I stand corrected.

[Hybrid tellies]

These are quite nice sets giving good pictures. They are one of the few batt/mains sets if not the only one to have done away with the heavy mains transformer, instead using a clever circuit that was called a pump start power supply. Very similiar to a modern chopper or switch mode power supply. They were very reliable and well worth saving.

[Welsh Anorak]

Hi
It is a tone switch - more use as symmetry!
Please be careful putting the back on - I remember one of my first successful teenage repairs was on one of these - until I tightened the last screw - psssssst.........oh dear.

Glyn

PS Simon - ISTR the GEC set also used a similar circuit.

[Zelandeth]

Afraid I'm on holiday in the States at the moment - but if when I get back in a couple of weeks nobody's tracked one down yet I do have the original user guide which includes schematics, scope traces and component descriptions. Will be a bit of a pest to scan as the sheets are large, sure I could manage though if you need them.

As others have said, the mystery button is nothing more than a tone control.

The circuit is quite unconventional for a portable of its age, but actually works very well and does save a huge amount of weight compared to a transformer based power supply.

Two things worth being wary of though.

1. Make very, very sure that the tube neck is correctly located when securing the back of the case, otherwise it'll crack the CRT neck...not good!

2. If you're doing any running tests with the chassis out of the case, be aware that one of the HT rails is right on one of the edges of the PCB - positioned right in the correct place to zap the fingers of the uwary...can't remember precisely where, but I remember being warned about it by someone else and being very careful about it when I was working on mie.

[Heatercathodeshort]

Be very carefull if you have to remove the chassis, The front cabinet containing the CRT becomes top heavy and falls forward....Another pssssst and the tube neck sealing pip is a gonna.. J.

[Jimmyhaflinger]

Be careful, i think the chassis is live when the set is run from mains power!