Unknown parts - maybe from TVs ?

[Valvebloke]

I've picked up some stuff from a chap who used to repair TVs and among it were these three items (I've got a few of each one). The last items are thermistors I believe, but any further information about what their properties might be would be welcome (the little one has one red and one green dot painted on). The first item consists of a small metal can with a red insulator in one end and a single splash of green paint on the side. The second item looks like a shaped nylon shaft with an adjusting screw slot in one end, a steel (?) sleeve and a bulge on the other end. The ruler scale is in cm.

Thanks,

VB

[crustytv]

The first component shown is a diode and a wholly unreliable one at that, a change on sight component. I first came across a few failed ones of these in a PYE VT4. Red dot should denote Cathode.

No idea on the second item.

The last ones as you correctly state are thermistors, the CZ1 - CZ12A range. If you measure the diameter and length I can tell you exactly what type as the data manual for these is in the data library. At a guess I would suggest the larger is a CZ1.

[malcscott]

Second item looks like a tuning slug from a vhf tv tuner, Malc.

[sideband]

The first component shown is a diode and a wholly unreliable one at that, a change on sight component.

Yep....a selenium diode. They smell as bad as their larger brothers........

[Valvebloke]

Thanks for all this folks, I knew I could rely on you to clear the confusion. Thanks also for the warning about the selenium ! To be honest I wasn't expecting to use these things in anger - I was mostly just curious about what they might be. I'll probably donate them to the next convenient BVWS Bring And Buy.

VB

[raditechman]

The second item looks like a tuning slug that was used in later model VHF tuners, ones using I think PC97 and PCF801 valves.
They used to break and were a nuisance to change until quick method was found which normally worked and enabled replacement out in the field.
From memory I think it meant heating the end of small flat balded screwdriver and melt a slot into the slug, once cooled the screwdriver then unscrews the broken slug and a new one can be fitted.
Something like that.
If that failed dismantle tuner, longer job.

John

[nuvistor]

The second slug is from a Philips VHF tuner, they used to snap off. They were a bit fiddly to get the broken piece out but the easy to put the new ones in. Complete on a house call, no need to take the set or tuner to the workshop.

Some Ekco sets used them, if they set had to be transported there had to be no weight on the tuner knob, i.e. laying down on its face, the ride in the van would then break those slugs.

Frank

Edit, should have read Johns post more closely.

[Terrykc]

The last ones as you correctly state are thermistors, the CZ1 - CZ12A range. If you measure the diameter and length I can tell you exactly what type as the data manual for these is in the data library. At a guess I would suggest the larger is a CZ1.

The CZ1 - virtually universal in 300mA heater chains for several years - was slimmer and possibly longer than the thermistor shown.

It is more likely to be a CZ19, the one that frequently cracked in two in the Bush TV125 series if the mod hadn't been carried out.

If it is, I doubt that they can easily be found these days - probably nigh on impossible - so could be well worth hanging on to!