Bush VHF90A - UK Vintage Radio Repair and Restoration Discussion Forum

JoshWard · 2nd Aug 2011, 4:40 pm

Hi all,
The other evening I was chatting to Tas and conversation turned to his VHF90A and he was saying what a nice radio it was. I suddenly remembered I had one of these sets in my to do pile and once the Stella was done I thought I'd drag it out.
I bought it last year from a local antiques centre (now sadly gone 'upmarket', shop has halved in size and prices have doubled!) for £10 and was working when I got home and plugged it in. Fast forward to a couple of days ago and I managed to find it after some rearranging of sets (it was buried between an Ultra Coronation Twin, a 1940s McMichael and a Pye portable!). Plugged it in and it was still a go-er although it was smoking a bit. Managed to get it apart fairly easily (although the dial had to be removed very slowly and gently) and had a look inside. A few waxies here and there but no horrors and fairly well laid out (the chassis is vertical). I also noticed some writing on the cardboard Bush label inside the set from 8th December 1962 which stated a new UCC85 had been fitted along with a silicone rectifier and a new audio coupling (THAT) cap.

First job was to change all the dodgy looking wax caps, whilst I was at it I changed the small (0.002µF) cap across the mains for a nice new X2 one. I found THAT cap which had been replaced by a lovely Mullard mustard. I checked the voltage on the grid of the UL84 and there was nothing there so it was still functioning well.
I also checked all the resistors in the set and couldn't find one out of tolerance, a first for any set I have encountered. I managed to find the source of the smoke, some rubber insulation was wrapped around the speaker leads which had spent the last 50 years sitting against a power resistor. Some of this insulation (almost like a grommet around the two wires) had rubbed off on the resistor and was slowly smoking away. I scraped what I could off the resistor which sorted the smoking.

Next job was to look at this silicon rectifier that had been fitted. The old metal rectifier was still in place although disconnected. The 'new' component had been fitted well but with no surge limiting resistor. I found a good 100ohm resistor and fitted that in series with the diode mounted on a piece of tag strip. To fix the tag strip to the chassis I sadly had to remove the original rectifier.
I also mounted some tag strip on the valve side of the chassis as I had read horror stories of the pygmy lamps melting the plastic dial surround. I ordered some beefy 1k power resistors from RS and fitted one in series with the dial lamp which is now a tad dimmer.

All valve pins and sockets and the on/off/volume switch were then cleaned, also a replacement mains cable was fitted as the original had been cut short along with a fresh grommet where it entered the chassis as the old one was badly perished. Liking this set as much as I do I decided to treat it to a proper Clix two pin plug rather than the vulgar modern variety!

The cabinet was easily cleaned up. It was in immaculate condition when I bought the set and had only suffered some light mildew from being stored in the workshop over winter (I believe it had been stored near my oil heater so suffered hot and cold cycles). It came up fantastic with some T-Cut and the dial was cleaned in warm soapy water. The bright in the centre and the pointer came up immaculate with some Brasso. The trim in the front is slightly distorted but nowhere near as bad as some other examples I have seen. I didn't fancy removing all those clips that hold the baffle board in and potentially wrecking the cabinet in the process.

Overall I am really pleased with this set. It looks fantastic, is in great shape and sounds terrific and is sensitive too, no doubt helped by the three UF89s.
Just need the rather cool DAC70C now

Josh.

2nd Aug 2011, 5:39 pm

I have seen plastic expand when in a solvent (white spirit?) perhaps that would be a cure for the shrunken trim.

Quote:

I had read horror stories of the pygmy lamps melting the plastic

You can get 7W pigmy bulbs, I have some in the smaller bayonet that looks like yours, I only got tham a few months ago.

Bob_Moss · 3rd Aug 2011, 6:52 pm

A colleague recently bought a "Golf Ball" style LED lamp. The even illumination was most impressive and very little heat dissipation.
I think it was from CPC part number LP03052, although other styles are available..

JoshWard · 5th Aug 2011, 1:00 am

It seems the heat from the radio makes the trim go soft, it was on for about five hours today and the trim felt slightly spongy to the touch. Not much to do about that as it's an AC/DC radio after all. The dial area remained cool so I will keep my 1K power resistor in place. I did look into what other forum members had done and when (if, now it's being under-run) this lamp blows I will probably try an LED one.

Josh.

Tazman1966 · 7th Aug 2011, 12:04 pm

A nice radio and listening to mine as I type. Well done Josh

mark pirate · 7th Aug 2011, 3:53 pm

Quote:

Just need the rather cool DAC70C now

That has reminded me that i have one on the roundtuit pile, it has a good dial, but the plastic trim has shrunk quite a bit

Here's a photo to whet your appetite....

Mark

JoshWard · 8th Aug 2011, 11:01 am

Thanks Taz

Looks a nice project Mark, just a shame about the trim. I did wonder if some gentle heat and a bit of persuasion would make the trim soft enough to be adjusted but I didn't fancy trying it in case I made mine worse!

Josh.

2nd Aug 2011, 4:40 pm	#1
JoshWard Octode Join Date: Dec 2005 Location: Near Stowmarket, Suffolk, UK. Posts: 1,962	Bush VHF90A Hi all, The other evening I was chatting to Tas and conversation turned to his VHF90A and he was saying what a nice radio it was. I suddenly remembered I had one of these sets in my to do pile and once the Stella was done I thought I'd drag it out. I bought it last year from a local antiques centre (now sadly gone 'upmarket', shop has halved in size and prices have doubled!) for £10 and was working when I got home and plugged it in. Fast forward to a couple of days ago and I managed to find it after some rearranging of sets (it was buried between an Ultra Coronation Twin, a 1940s McMichael and a Pye portable!). Plugged it in and it was still a go-er although it was smoking a bit. Managed to get it apart fairly easily (although the dial had to be removed very slowly and gently) and had a look inside. A few waxies here and there but no horrors and fairly well laid out (the chassis is vertical). I also noticed some writing on the cardboard Bush label inside the set from 8th December 1962 which stated a new UCC85 had been fitted along with a silicone rectifier and a new audio coupling (THAT) cap. First job was to change all the dodgy looking wax caps, whilst I was at it I changed the small (0.002µF) cap across the mains for a nice new X2 one. I found THAT cap which had been replaced by a lovely Mullard mustard. I checked the voltage on the grid of the UL84 and there was nothing there so it was still functioning well. I also checked all the resistors in the set and couldn't find one out of tolerance, a first for any set I have encountered. I managed to find the source of the smoke, some rubber insulation was wrapped around the speaker leads which had spent the last 50 years sitting against a power resistor. Some of this insulation (almost like a grommet around the two wires) had rubbed off on the resistor and was slowly smoking away. I scraped what I could off the resistor which sorted the smoking. Next job was to look at this silicon rectifier that had been fitted. The old metal rectifier was still in place although disconnected. The 'new' component had been fitted well but with no surge limiting resistor. I found a good 100ohm resistor and fitted that in series with the diode mounted on a piece of tag strip. To fix the tag strip to the chassis I sadly had to remove the original rectifier. I also mounted some tag strip on the valve side of the chassis as I had read horror stories of the pygmy lamps melting the plastic dial surround. I ordered some beefy 1k power resistors from RS and fitted one in series with the dial lamp which is now a tad dimmer. All valve pins and sockets and the on/off/volume switch were then cleaned, also a replacement mains cable was fitted as the original had been cut short along with a fresh grommet where it entered the chassis as the old one was badly perished. Liking this set as much as I do I decided to treat it to a proper Clix two pin plug rather than the vulgar modern variety! The cabinet was easily cleaned up. It was in immaculate condition when I bought the set and had only suffered some light mildew from being stored in the workshop over winter (I believe it had been stored near my oil heater so suffered hot and cold cycles). It came up fantastic with some T-Cut and the dial was cleaned in warm soapy water. The bright in the centre and the pointer came up immaculate with some Brasso. The trim in the front is slightly distorted but nowhere near as bad as some other examples I have seen. I didn't fancy removing all those clips that hold the baffle board in and potentially wrecking the cabinet in the process. Overall I am really pleased with this set. It looks fantastic, is in great shape and sounds terrific and is sensitive too, no doubt helped by the three UF89s. Just need the rather cool DAC70C now Josh. Attached Thumbnails

3rd Aug 2011, 6:52 pm	#3
Bob_Moss Pentode Join Date: Mar 2003 Location: Mansfield Woodhouse, Nottinghamshire, UK. Posts: 215	Re: Bush VHF90A A colleague recently bought a "Golf Ball" style LED lamp. The even illumination was most impressive and very little heat dissipation. I think it was from CPC part number LP03052, although other styles are available.. __________________ I was so upset that I cried all the way to the chip shop.

5th Aug 2011, 1:00 am	#4
JoshWard Octode Join Date: Dec 2005 Location: Near Stowmarket, Suffolk, UK. Posts: 1,962	Re: Bush VHF90A It seems the heat from the radio makes the trim go soft, it was on for about five hours today and the trim felt slightly spongy to the touch. Not much to do about that as it's an AC/DC radio after all. The dial area remained cool so I will keep my 1K power resistor in place. I did look into what other forum members had done and when (if, now it's being under-run) this lamp blows I will probably try an LED one. Josh.

7th Aug 2011, 12:04 pm	#5
Tazman1966 Nonode Join Date: May 2006 Location: St Albans, Herts, UK. Posts: 2,193	Re: Bush VHF90A A nice radio and listening to mine as I type. Well done Josh __________________ All the very best, Tas

8th Aug 2011, 11:01 am	#7
JoshWard Octode Join Date: Dec 2005 Location: Near Stowmarket, Suffolk, UK. Posts: 1,962	Re: Bush VHF90A Thanks Taz Looks a nice project Mark, just a shame about the trim. I did wonder if some gentle heat and a bit of persuasion would make the trim soft enough to be adjusted but I didn't fancy trying it in case I made mine worse! Josh.