Bush VHF80

[Amie]

Hi all.

I haven't completely pulled this apart yet but I'm looking for advice on a repair that needs doing on the tuner in a VHF80 Bush.

Basically, the tuning for the VHF band is two inductor cores on a piece of dial cord threaded into the screening can of the tuner that is pulled out or allowed to retract when the tuning is operated.

It has broken internally.

   

   

The trader sheet I have says that this cord is an assembly and has to be replaced as one, but I'm hoping that it can be repaired somehow?

Has anyone any experience of this?

Thanks.
Amie.

[boater sam]

It should be quite easy to remove the cord and the coil slugs and replace the cord, bead cord works well.
You will have to get the length between the slugs and the length to the spring very accurate as the original as one coil is the aerial tuning and the other is the oscillator frequency.
 Sam.

[Murphyv310]

It's really fiddly job to get right.
I've got quite thick fingers and it took ages to do one of this type of tuner some years ago. Easier for someone young with dexterity and good eyesight, most of the UK Radio factories employed lassies in assembly due to better dexterity than men, so I think you should be able to fix this quite easily Amie.

[Amie]

Are the two cores bonded to the cord somehow? The spacings being critical would make it necessary to get it right first go....

[Murphyv310]

Hi.
The one I did wasn't in a Bush TBH but looks the same in the diagram, the cores were bonded with a small dab of what looked like contact adhesive, a soaking with cellulose thinner removed is easily.

[Amie]

Thanks Trevor, I'll give it a go, provided I can measure the distance between the two cores it should be OK

(I hope ....)

Amie.

[Geordie McBoyne]

The attachment shows a Bush A199 FM tuner unit. It is possible to remove the FM tuner assembly without the need to re-string the tuning drive. 

Geordie McBoyne.

[Amie]

Thanks Mr McBoyne. The trader sheet I have for that chassis infers its possible to do that, I've also got the 81 which is basically the same just a large wooden cabinet.

I've been offered a NOS replacement cord and slug assembly to copy and return if I can, buy if I can't . I think mine got jammed and pulled through the first core.

I'd like to get it back in order, its one that's been in daily use, its better than most of the time for sensitivity.

Thanks,
Amie

[Murphyv310]

The attachment shows a Bush A199 FM tuner unit. It is possible to remove the FM tuner assembly without the need to re-string the tuning drive. 

Geordie McBoyne.

Yes you can remove the tuner which is exactly what I did.
The issue is how fiddly it is to do and getting it right on the first attempt when the cord is snapped internally.

[Kalee20]

I do have a reel of RS dial-drive cord, glass-fibre core (so doesn't stretch) and braided nylon outer - PM me if you would like a length.

(Looking at the diagrams, it does look a so-and-so to work on...)