Wax Capacitor - Bush TR90C (208)

[Micker]

ok Jeff - thats why I'm here to learn off chaps like you, if what you say is correct it shouldn't be too much bother to resolder it back into position, I dont chuck anything just in case. I'll go and get a pic taken of both sides of the chassis.

[ppppenguin]

I hope you haven't damaged them during removal. While they are fine if left alone they are not very robut mechanically.

On the subject of photos, when doing a repair or restoration take lots of them. Before, during and after. They solve a lot of memory problems. I also print a fresh copy of service data so I can scrawl notes to my hearts content. If I'm changing a few (or a lot in the case of a TV) capacitors I'll mark them off with a highlighter as I do them.

[Micker]

Here's some pics Jeff, as you can see its labelled in the batt compartment as TR90C but has the extra waveband switch for 208, which I'm lead to believe may make it a Mk11. Both under-chassis and top pics show this is the only type of that particular cap. biro indicates where it lives. - cheers again for your invaluable input.
off to work now - another day etc. etc.

[ppppenguin]

The black tubular caps are 'orrible 'unts. You may get away with them in a transistor set but it's normally replace on sight. The Mullard "mustard" will be fine. Electrolytics may be OK now but should all be changed.

The original battery was a PP7 whcih is no longer available. Either change the snaps and use an alkaline PP3 or 6x AA cells in a holder. I think it's just about possible to get 6x AA cells in an old PP7 box.

When taking photos it's usually better not to use flash. Try it and see, ideally in decent light.

Incidentally, I don't know this set and my own interests are more TV than radio so I'm only giving standard basic guidance. I'm sure that others will be able to give better and more specific advice.

[Micker]

thanks again Jeff - your 'basic guidance' is really appreciated.

[ppppenguin]

Although I'm supposedly fairly expert, I can get things wrong as easily as the next man. Opinions will vary too.

Mick, just realised I was up your way in September. I have a friend in Shevington who I stayed with en route to the Lakes. We went here for dinner: http://bindiaspull.uk/ Got chatting with the owner and found we'd both studied at Imperial College and he knew my favourite Indian restaurant in London. Small world.

[Micker]

literally just round the corner - it is indeed a small world.... but you wouldn't want to hoover it!

[Nick]

The original battery was a PP7 whcih is no longer available. 

https://smallbattery.company.org.uk/sbc_pp7.htm

Out of stock ATM but worth asking... (even at that price)

[Murphyv310]

Hi.
There are many new to this hobby that are unaware that silver mica capacitors are usually perfectly OK.
It's not their fault as we talk about waxies, so seeing a wax covered capacitor it's usually change on sight.
Many of us experienced restorers will tell others that.
A 9volt operated transistor radio really doesn't need this across the board advice, the low impedance of transistor devices is not going to be effected by a few Meg ohms leakage. My advice is only replace if there is a fault like noise or hiss on the audio. The biggest issue is dried out electrolytic caps or leaky ones. Measure the quiescent current on the set and if out of spec then investigate. Restoration is less of a word with these sets it's more like fault finding and service, a different kettle of fish.

[Crackle]

I usually clean dirty wax capacitors with WD40 squirted  onto a bit of kitchen roll.

Gus.

I use this same method as well, but in rare cases some caps do have the printing on the outside of the wax.
In which case all the print can disappear.
Mike