Has your analogue Roberts radio become difficult to tune?
The Roberts Revival range including the R250 and R760 can develop a fault with the drive cord and become stiff to tune. This may occur towards one end of the range and a clicking noise can be heard when the knob is turned. You may be tempted to pull off the control knob and find the whole spindle comes away leaving a tangled cord behind!
Don’t throw it away, it may be possible to fix with a little patience if you follow the steps below.
- First remove telescopic aerial and then the top dial and main chassis by undoing the two screws either side next to the handle. For the R250 remove the wooden blocks that hold the dial in place.
- Remove both volume and tuning knobs by gently pulling them off – the tuning spindle may pull out as well – if it does be careful not to break the cord. If the volume control won’t move, place some masking tape on the dial to avoid damage and use a flat blade to lever the knob from beneath.
- Prise off the plastic dial ‘glass’ using a small screw driver to lift it free. It’s held in place by double sided sticky tape and fairly flexible. Take care not to scratch the print underside. The drive cord should now be visible with the four pulleys and drive spindle.
- Look at the photos below to see where the cord should run if it’s come away. In many cases the cord catches under the drive spindle and becomes tangled causing the fault. The drive spindle needs at least three neat turns of cord without overlapping.
- Check the cord is located correctly on the large drive wheel. If the spring tension is too tight the cord tends to tangle on the drive spindle.
- To thread the cord start by making sure the drive wheel is fully one end and align the cord so the pointer (red below) is at the corresponding end of the dial.
- Ensure the cord is correctly wound around the spindle – image 7 shows the cord returning to the drive wheel from the lower end. If you have it the other way round the pointer will move in the wrong direction when the control is turned. It should move to the right when turned clockwise.
-
- Drive spindle
-
- Drive wheel
-
- Drive spindle with cord
If your cord has snapped the replacement will need to be the same thickness. Braided nylon drive cord is best as it does not stretch. Fishing line can work if you can’t find proper drive cord – the spring will help keep tension.
PP9 Battery eliminator
As PP9 batteries are becoming difficult to buy at a reasonable price here are some alternative options.
- Buy a PP9 battery adapter which houses 6 x AA cells – these are available for less that £10 on Ebay an other sites.
- Use an old PP9 battery housing and place an AA cell adapter inside – see pics below. A plastic case works best.
- Buy a Replica Ever Ready PP9 Battery Adapter – these are also available via eBay and cost £15 with postage in the UK.
- Use rechargeable NiMH AA cells in the above to avoid using disposable alkaline cells
28/03/2015 at 2:57 pm
I found that whatever I did would not stop the cord overlapping sometimes and jamming. I eventually solved it by making and fitting a small plastic bridge over the cord just before it winds onto the drive spindle (on image 7 that would be between the spindle and the top guide wheel). This ensures that the cord stays tight against the back of the spindle and any overlapping does not hinder the release of the cord.
It worked for me!
29/03/2015 at 12:13 am
Colin – Thanks for your suggestion. Adding a bridge to guide the cord sounds an excellent idea – had one radio where the plastic pulley spindles had bent over slightly causing the cord to keep tangling. Even reducing spring tension still tangled occasionally, so the bridge would have helped.
17/02/2017 at 5:16 pm
I’ve a R550 that on switch on drifts off signal after a minute or so. Retuning cures but it then drifts again. After a few “drifts” it settles down on tune for the rest of the day. Is this a cord issue or something deeper in the front end, do you think. ?
17/02/2017 at 6:16 pm
If the drift is on FM only it may be the AFC (auto frequency control) circuitry that’s at fault. I’ve not had this problem on a Roberts R250/R550 so would need to look at the circuit for clues or if it has afc.
It could just be a taught drive cord that’s being pulled slowly by the small spring in the centre of the drive wheel. Is the tuning control tighter to turn than the volume? Or does it get tighter up either end of the band?
28/06/2023 at 7:27 pm
My radio has stopped tuning in to the radio channels.
29/06/2023 at 5:23 am
There are a few things you can try to find out why your radio won’t tune. Has it stopped tuning on all wavebands or is this on FM only? If all wavebands are affected, disconnect power and open the back of the R250, if necessary remove the small screws holding the back cover, and check if the large black tuning gear wheel turns when you try tuning. The dial cord may have broken. If only FM is affected it’s probably a fault on the circuit board with the oscillator and will need repair.
22/11/2023 at 6:20 pm
Hi Rick.
The drive cord on my Roberts R 717 has snapped, I was trying to fix it but no luck. Do you have any images of where on the drive wheel the spring should be and how to guide the cord around the smaller wheels. I think I could manage it if I get new cord and can see more clearly how to put it on. Thank you.
Caroline.
23/11/2023 at 11:16 am
Hi Caroline, Radio Museum’s R717 looks similar to the R250 chassis as I featured in this post. Have you tried following the steps I suggested and the photos which show the drive wheel and spring arrangement?
I don’t have an R717 to offer more specific advice sorry.
11/12/2024 at 10:20 pm
Hi
My wife’s Roberts R25 (owned since mid 80’s) has stopped tuning. I found the loose end of the drive cord under the tuning knob. Is it an easy fix? I need to replace the antenna too, as the end snapped off. Do you know if parts are still available?
Thanks
11/12/2024 at 11:32 pm
The R25 is a nice radio and well worth fixing. Drive cord is available cheaply in small lengths on eBay – search for Vintage Radio Tuning Dial Drive Cord. Check the diameter you need – it’s likely around 0.6mm. There are instructions available in the technical data sheet from archive.org. Replacement telescopic aerials are more tricky to source and can be more expensive. I think the R250 has a similar aerial – Roberts technical services do supply some spare parts for their radios and may be able to suggest alternatives. Good luck.
12/12/2024 at 11:34 am
Hi
Thanks, that’s really helpful. I’ve got it apart and found the cord on ebay. I’ll probably just mend and diy-make-do with the aerial as it’s only lost its tip section.
One last query. I don’t think the metal crimps for the drive cord can be salvaged. Any suggestions what to search for, or alternatives? Maybe I’m overthinking it, just tie a knot?
Thanks again,
Chris
12/12/2024 at 2:16 pm
Yes, a simple knot works fine. Terminal crimps can damage the cord if not careful. I checked the R250 and unfortunately it uses a shorter telescopic aerial with 10mm diameter. If it’s just the tip missing and you have the tip thread exposed I’ve used a small plastic bead or similar. Drill a small hole and cut a thread in it using the tip then reseat with a dab of epoxy. It makes it easy to pull the aerial out and reduces danger of poking an eye.
30/12/2024 at 2:09 pm
Hi
A short update.
Fitted the cord today (0.6mm £4 ebay).
After the cord slipping on the spindle, I put an extra couple of turns of cord on the spindle.
All working fine now. Listening to Radio 3 as I write….
Thanks again,
Chris
30/12/2024 at 3:42 pm
Excellent to hear you’ve fixed the radio. Yes, it needs at least 3 turns around the drive shaft. There’s also a small spring fitted on the R250 – I can’t remember if the R25 has one – which applies some tension. Thanks for the update, always good to know.
30/12/2024 at 8:11 pm
Hi again,
It crossed my mind to look into some kind of pp9 to pp3 conversion. (pp9’s seem to be hard to come by these days).
This would help with my wife’s R25 and our similar aged Rambler.
I’ve seen 2x packs of pp9 connectors and 5x packs of pp3 connectors on ebay but I’m unsure of the practicalities. Is there a steer you can help with?
Thanks,
Chris
30/12/2024 at 9:18 pm
Hi Chris, I’ve been looking at PP9 replacements too for the same reason. Here’s a ready made option on Ebay https://www.ebay.co.uk/itm/326350662916 Using a set of AA cells will last much longer than a PP3. You can hide the 6 AA cells inside an old PP9 case. I’ve added some pics to the post above.
27/02/2025 at 12:54 pm
Hi again.
Sorry for late reply.
I bought the AA option via your link.
It is an excellent replacement and I’ll get a another one for the Rambler.
Thanks again for the link.