Roberts RCM1

[Digilogue]

Hi does anyone know how to make the radio come on rather than the alarm sound when the alarm is set please?

[Paul_RK]

Hi and welcome,

I don't think there's a way without modifying the circuitry. Couldn't find a user manual so I've just been playing with my RCM1 - it's not in regular use and I couldn't remember how it works . Radio and the beeping alarm come on together, and I suppose the idea is that you get woken up no matter what the radio station is broadcasting, or whether the set is tuned to a station at all, then just move the little slider switch to the left if you want to shut off the alarm and carry on listening.

Paul

[Digilogue]

Thanks Paul. There's a manual here: https://golbornevintageradio.co.uk/forum...p?tid=3101 but I can't access it because I'm a newbie member apparently. I found a service manual but I don't see a way to upload that here. I'll have to study it a bit longer.
Dave.

[Mark Hennessy]

Hi Dave, and welcome to the forum.

That manual is also a service manual, albeit one that came from the radio and servicing books. I don’t think it contains anything in the way of user instructions, sadly.

If your manual is a genuine Roberts one, then that would compliment our one nicely. But only upload it if you’re happy with our terms of usage for The Archive (I say that because not everyone is, which is fair enough). Attach it here if you like, and I can move it to The Archive.

Cheers,

Mark

[Digilogue]

Thanks Mark. It's quite likely it's the same manual then, but I don't see a way to attach it here. Here's the link to it though: https://www.vintage-radio.net/forum/show...p?t=110684
Dave.

I like your web site btw.

[Mark Hennessy]

Hi Dave,

Yes, that's my scan - the same one as is in The Archive here. So that doesn't get you any further forward, sadly. Like Paul, I suspect that a modification might be required.

Fortunately, that's easy - just lift the end of R29 or C35, or perhaps R38 - the exact component you choose can be a matter of whatever easiest.

I've been looking for clues in the datasheet for the MM5316 - http://pdf.datasheetcatalog.com/datashee...223_DS.pdf

It only offers 1 alarm output (pin 25). This goes high and starts the phase-shift oscillator (TR5). Also, via D5, it turns on the radio via TR3 and 4. Pin 39 is a 1Hz output, which is used to modulate the oscillator.

Looking at the way Roberts have designed it, it doesn't look like there's a way to separate those functions - so the radio and alarm coming on together is what they intended.

I could dig my example out from the attic and investigate further if required, but I the more I look, the more a mod is looking likely, I'm afraid.

Thank you for the complement - I really must devote a bit of time to finishing some of the articles I've got in the pipeline.

All the best,

Mark

[Digilogue]

Thanks Mark that's much appreciated. No need to dig your example out from the attic.

Regards,
Dave.