Replacing caps in dansette RG30 - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Al (astral highway) · 25th Nov 2008, 9:09 pm

Quote:

Originally Posted by vascoprat

I'm a bit disappointed with the LW reception, which is very noisy. Presumably this is an aerial problem as well?

LW reception is quiet compared to the same station on medium wave. The two sets I have with ferrite aerials, a Kolster Brandes and a Roberts of about the same vintage, have very poor reception on both wavebands compared to a set of a similar vintage with a 15 metre longwire around the bedroom picture rail.

This is hardly surprising.

On the noise problem, please see a very recent thread on this by searching CFT's - there's a lot of encouraging advice and home-brew research in there!

vascoprat · 25th Nov 2008, 10:51 pm

My Grundig transistor radio from the early 70s, which I recently repaired, works fantastically on LW at 198KHz. So I guess there's probably something wrong. I moved the coil along the rod but it makes little if no difference. Any suggestions about how to start checking for things which may cause this?

Nickthedentist · 25th Nov 2008, 11:12 pm

I'm sorry to say that this is where my radio knowlede ends

Have you checked that the waveband switch is clean? Band switching doesn't seem complicated; seems to involve selecting L5 or L6 on the ferrite rod, and bringing C6 into play.

Has anyone else got one of these to let us know what LW performance is like?

Good luck,
Nick.

vascoprat · 26th Nov 2008, 10:53 am

Nick
I took your advice and took a look at the band switch. One of the screening wires I had resoldered (badly) had come away. I re-soldered it and hopefully did a better job this time and LW sounds much better now. I am going to put that earth wire in which reduces the background hiss even more. So I think everything will be OK now.
Thanks
vasco

vascoprat · 26th Nov 2008, 8:09 pm

Astral Highway
Thanks for the info about CFTs. If my room light is on (energy-saving) and I move my hand near to the chassis the noise increases enormously, but this does not happen when the light is switched off.

Sideband · 26th Nov 2008, 10:13 pm

Quote:

Originally Posted by vascoprat

It's brown, black, red which is 1000pF. According to the schematic it should be 200 pF.

...but if you read the colours the other way around ...red, black, brown, this is 200 pF.....!

With some of these banded capacitors, the first colour band or blob is sometimes thicker.

Rich.

vascoprat · 1st Dec 2008, 6:43 pm

I thought of that but they both have a silver-grey blob as well and if you read them both with the silver blob to the right then they come out as I said before and don't agree with the schematic. Surely you can't read one of them in one direction and the other in another?

25th Nov 2008, 10:51 pm	#22
vascoprat Tetrode Join Date: Sep 2008 Location: Middlesbrough, North Yorkshire, UK. Posts: 72	Re: Replacing caps in dansette RG30 My Grundig transistor radio from the early 70s, which I recently repaired, works fantastically on LW at 198KHz. So I guess there's probably something wrong. I moved the coil along the rod but it makes little if no difference. Any suggestions about how to start checking for things which may cause this?

25th Nov 2008, 11:12 pm	#23
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,864	Re: Replacing caps in dansette RG30 I'm sorry to say that this is where my radio knowlede ends Have you checked that the waveband switch is clean? Band switching doesn't seem complicated; seems to involve selecting L5 or L6 on the ferrite rod, and bringing C6 into play. Has anyone else got one of these to let us know what LW performance is like? Good luck, Nick.

26th Nov 2008, 10:53 am	#24
vascoprat Tetrode Join Date: Sep 2008 Location: Middlesbrough, North Yorkshire, UK. Posts: 72	Re: Replacing caps in dansette RG30 Nick I took your advice and took a look at the band switch. One of the screening wires I had resoldered (badly) had come away. I re-soldered it and hopefully did a better job this time and LW sounds much better now. I am going to put that earth wire in which reduces the background hiss even more. So I think everything will be OK now. Thanks vasco

26th Nov 2008, 8:09 pm	#25
vascoprat Tetrode Join Date: Sep 2008 Location: Middlesbrough, North Yorkshire, UK. Posts: 72	Re: Replacing caps in dansette RG30 Astral Highway Thanks for the info about CFTs. If my room light is on (energy-saving) and I move my hand near to the chassis the noise increases enormously, but this does not happen when the light is switched off.

1st Dec 2008, 6:43 pm	#27
vascoprat Tetrode Join Date: Sep 2008 Location: Middlesbrough, North Yorkshire, UK. Posts: 72	Re: Replacing caps in dansette RG30 I thought of that but they both have a silver-grey blob as well and if you read them both with the silver blob to the right then they come out as I said before and don't agree with the schematic. Surely you can't read one of them in one direction and the other in another?