Repairing a Roberts R900. - UK Vintage Radio Repair and Restoration Discussion Forum

Fray Bentos · 31st Mar 2008, 2:50 pm

Hi again,

Now it's time to prove your worth!!

I've picked up a very tidy Roberts R900 No : 15531, the one with the slightly jutting out speaker grille.

It is all complete, needs a clean, BUT the tuning cord is snapped. I knew about this when buying it and I want to have a go myself at fixing it, then that's it it should be ready to go.

I am limited in the electronics side of things but ok and happy to have a go at the more practical, take apart and back together jobs, so this Roberts seemed ideal.

So, as the title suggests, please tell me it easy.......over to you, and many thanks as usual for any help you can give.

Regards

Richard

Steve_P · 31st Mar 2008, 2:53 pm

Tuning Cord - keep a swear box handy and you can use fishing cord - visit your local anglers store.

Is the ON/OFF Button OK?

Cheers,

Steve P

Fray Bentos · 31st Mar 2008, 3:50 pm

Thanks for the reply Steve, yes all the buttons are ok the on/off is particularly crisp and definate in its action (was this a favourite to break??)

It works fine, the odd crackle on the volume, not there all the time on turning, aerial complete and extends fine, no kinks.

Cord obviously broke whilst on Classic FM !! and this is crystal clear.

Are there any links or printouts to doing this cord, I've plenty of fishing line....another hobby !!

Thanks again.

Richard

howard · 31st Mar 2008, 9:48 pm

Hello Richard,

This will be a fiddly job ! I don't have the R900 service data sheet so there are pics below of the route of the cord. You'll need to take the set apart first and remove the perspex dial as described here ...

https://www.vintage-radio.net/forum/...ad.php?t=11601

Before I dismantled the set I moved the cursor right over to the 88 MHz VHF end of the scale, just beyond Radio 1. There are 3 turns of cord around the tuning spindle. I suggest you remove the existing cord and make up a new one identical in length with loops ready tied on the ends. You'll also have to remove the pointer from the old cord and put it back in the position shown. Once the cord is in place check that the pointer lines up with wavelengths of stations and adjust it if it doesn't.

While you're inside squirt a little Servisol 10 (from Maplins) into the volume and tone pots and into the ends of the on/off and wavebands switches.

Good luck, and mind your language !

Howard

Fray Bentos · 31st Mar 2008, 9:57 pm

Cheers Howard and Steve, I knew the forum would come up trumps. Howard, or anyone, do you have any reccomendation on the type of cord I need to be after and where I can get some from ? or is the fising line ok, although wouldn't this be too shiny for grip purposes etc.

Thanks again,

Richard

howard · 31st Mar 2008, 10:00 pm

Hello Richard,

I would've thought a fairly heavy guage fishing line would be fine.

Howard

Station X · 31st Mar 2008, 10:00 pm

I use Flyline Backing. To be specific Golden Marlin New Super Formula 20lbs FLI-51020. I haven't tried monofilament line.

Fray Bentos · 1st Apr 2008, 6:32 am

Many thanks for all the advice so far chaps. Is there a service sheet for the R900 doing the rounds?...couldn't locate one on the service data forum.
Thanks gain,

Richard

31st Mar 2008, 2:50 pm	#1
Fray Bentos Triode Join Date: Feb 2008 Location: Buckingham, Bucks. UK. Posts: 23	Repairing a Roberts R900. Hi again, Now it's time to prove your worth!! I've picked up a very tidy Roberts R900 No : 15531, the one with the slightly jutting out speaker grille. It is all complete, needs a clean, BUT the tuning cord is snapped. I knew about this when buying it and I want to have a go myself at fixing it, then that's it it should be ready to go. I am limited in the electronics side of things but ok and happy to have a go at the more practical, take apart and back together jobs, so this Roberts seemed ideal. So, as the title suggests, please tell me it easy.......over to you, and many thanks as usual for any help you can give. Regards Richard

31st Mar 2008, 2:53 pm	#2
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Roberts R900 - please tell me this is going to be easy!! Tuning Cord - keep a swear box handy and you can use fishing cord - visit your local anglers store. Is the ON/OFF Button OK? Cheers, Steve P __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

31st Mar 2008, 3:50 pm	#3
Fray Bentos Triode Join Date: Feb 2008 Location: Buckingham, Bucks. UK. Posts: 23	Re: Roberts R900 - please tell me this is going to be easy!! Thanks for the reply Steve, yes all the buttons are ok the on/off is particularly crisp and definate in its action (was this a favourite to break??) It works fine, the odd crackle on the volume, not there all the time on turning, aerial complete and extends fine, no kinks. Cord obviously broke whilst on Classic FM !! and this is crystal clear. Are there any links or printouts to doing this cord, I've plenty of fishing line....another hobby !! Thanks again. Richard

31st Mar 2008, 9:48 pm	#4
howard Nonode Join Date: May 2005 Location: Godalming, Surrey, UK. Posts: 2,593	Re: Roberts R900 - please tell me this is going to be easy!! Hello Richard, This will be a fiddly job ! I don't have the R900 service data sheet so there are pics below of the route of the cord. You'll need to take the set apart first and remove the perspex dial as described here ... https://www.vintage-radio.net/forum/...ad.php?t=11601 Before I dismantled the set I moved the cursor right over to the 88 MHz VHF end of the scale, just beyond Radio 1. There are 3 turns of cord around the tuning spindle. I suggest you remove the existing cord and make up a new one identical in length with loops ready tied on the ends. You'll also have to remove the pointer from the old cord and put it back in the position shown. Once the cord is in place check that the pointer lines up with wavelengths of stations and adjust it if it doesn't. While you're inside squirt a little Servisol 10 (from Maplins) into the volume and tone pots and into the ends of the on/off and wavebands switches. Good luck, and mind your language ! Howard Attached Thumbnails Last edited by howard; 31st Mar 2008 at 10:10 pm.

31st Mar 2008, 9:57 pm	#5
Fray Bentos Triode Join Date: Feb 2008 Location: Buckingham, Bucks. UK. Posts: 23	Re: Roberts R900 - please tell me this is going to be easy!! Cheers Howard and Steve, I knew the forum would come up trumps. Howard, or anyone, do you have any reccomendation on the type of cord I need to be after and where I can get some from ? or is the fising line ok, although wouldn't this be too shiny for grip purposes etc. Thanks again, Richard

31st Mar 2008, 10:00 pm	#6
howard Nonode Join Date: May 2005 Location: Godalming, Surrey, UK. Posts: 2,593	Re: Roberts R900 - please tell me this is going to be easy!! Hello Richard, I would've thought a fairly heavy guage fishing line would be fine. Howard

31st Mar 2008, 10:00 pm	#7
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Roberts R900 - please tell me this is going to be easy!! I use Flyline Backing. To be specific Golden Marlin New Super Formula 20lbs FLI-51020. I haven't tried monofilament line. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

1st Apr 2008, 6:32 am	#8
Fray Bentos Triode Join Date: Feb 2008 Location: Buckingham, Bucks. UK. Posts: 23	Re: Roberts R900 - please tell me this is going to be easy!! Many thanks for all the advice so far chaps. Is there a service sheet for the R900 doing the rounds?...couldn't locate one on the service data forum. Thanks gain, Richard