Roberts RIC 2 not working - UK Vintage Radio Repair and Restoration Discussion Forum

WilliamTK1974 · 26th Mar 2017, 1:54 am

Hi everyone,

The question is about my Roberts RIC 2. When I got it a few years ago, it appeared to have been stored in less than ideal conditions. It was dirty, the speaker frame had some rust, and the dial was in dire need of a scrub. I took it apart and cleaned it, and it started working.

I used an inexpensive AC/DC adaptor to power it at less than 9V, and it seemed to work quite well. I used it as a bedside MW DX radio for a long time and it didn't disappoint. I could hear just the slightest hint of a hum in the sound and suspected that the cheap power supply was putting some noise into the circuit. It didn't make things unlistenable, so I gave it little thought.

I decided to turn it on the other day using a 9V battery. Nothing happened. The battery isn't a PP9, but it was fully charged, so it should have been enough to get something to happen. I took it apart and gave the switch a clean, but nothing changed.

So, what's a good plan for doing an orderly check of the radio to find what's wrong with it? I would like to be able to bring it back to life.

Thank you,
-William

julie_m · 26th Mar 2017, 2:37 am

What do you have available, in terms of equipment? A soldering iron and a multimeter are pretty much essential. (Get simple ones to begin with; you can upgrade later.)

Check for audio at the clockwise end of the volume control potentiometer, using an oscilloscope or audio amplifier. That will eliminate half of the circuit -- either the RF / IF stages, or the audio stages -- in one go .....

WilliamTK1974 · 26th Mar 2017, 3:24 am

I do have soldering iron and multimeter, as well as knowing how to use them, but that's pretty well all I have at this time.

julie_m · 26th Mar 2017, 4:14 am

You could use a set of powered computer speakers, or an amplifier, or almost anything with an AUX IN and a speaker, to listen for a signal at the volume control.

60 oldjohn · 26th Mar 2017, 11:49 am

You have already cleaned the switch, the other part worth doing is the Earphone socket switch it is a weak point.

John.

mhennessy · 26th Mar 2017, 12:00 pm

I've found these sets to be very reliable indeed, and what problems I have had were caused by tin whiskers in the output transistors.

To quickly test for this, temporarily unclip them from the heat sink clip so the cases are no longer connected to the chassis.

Of course, this set has one of those notoriously unreliable earpiece sockets. So if there's absolutely nothing at all from the loudspeaker - not even a click at power-up - then that's a good place to start. You can bridge the contact to test, and often a good dose of switch cleaner and a gentle wiggle with a tooth pick or similar can sort them out. Replacements are available from Partridge Electronics.

Edit: Posts crossed...

WilliamTK1974 · 5th Apr 2017, 3:56 am

I'm not even getting a pop from the speaker when I switch it on. I bought a PP9 battery to simplify things a bit. It tests quite good, so the set should get power.

Is the mains socket in the rear of the radio a potential trouble spot? Mine appears quite corroded. Also, I inserted the tip of a metal screwdriver in between the two contacts of the adaptor socket. Some crackling ensued from the speaker, and I was able to tune in a few stations. Sound was robust but rather crackly, and reception less than ideal, but that could be due to the proximity of my computer and some other noisy items.

Thank you,
-William

wireless_john · 5th Apr 2017, 7:56 am

That's a point. Is there a switch on the mains socket that disconnects the battery when a plug is pushed in - and reconnect it when unplugged? I have a Grundig Hit Boy that has one. If so, it may not be reconnecting the battery.

Here's another thread on the same subject:

https://www.vintage-radio.net/forum/...ad.php?t=77521

John

mhennessy · 5th Apr 2017, 8:20 am

Quote:

Originally Posted by WilliamTK1974

Is the mains socket in the rear of the radio a potential trouble spot? Mine appears quite corroded. Also, I inserted the tip of a metal screwdriver in between the two contacts of the adaptor socket. Some crackling ensued from the speaker, and I was able to tune in a few stations.

You've answered your own question.

The fact you normally run the set with an external DC power supply adaptor is the clue; the contacts that normally pass current from the battery are held apart when the plug is inserted, so they have tarnished. 30 seconds with some switch cleaner or similar is the answer.

If in doubt, use your multimeter to verify...

WilliamTK1974 · 6th Apr 2017, 4:08 pm

The radio is back to life and running hum-free with the PP9 battery. Thanks to those who helped out with this.

26th Mar 2017, 1:54 am	#1
WilliamTK1974 Tetrode Join Date: Feb 2013 Location: Chattanooga, Tennessee, USA Posts: 59	Roberts RIC 2 not working Hi everyone, The question is about my Roberts RIC 2. When I got it a few years ago, it appeared to have been stored in less than ideal conditions. It was dirty, the speaker frame had some rust, and the dial was in dire need of a scrub. I took it apart and cleaned it, and it started working. I used an inexpensive AC/DC adaptor to power it at less than 9V, and it seemed to work quite well. I used it as a bedside MW DX radio for a long time and it didn't disappoint. I could hear just the slightest hint of a hum in the sound and suspected that the cheap power supply was putting some noise into the circuit. It didn't make things unlistenable, so I gave it little thought. I decided to turn it on the other day using a 9V battery. Nothing happened. The battery isn't a PP9, but it was fully charged, so it should have been enough to get something to happen. I took it apart and gave the switch a clean, but nothing changed. So, what's a good plan for doing an orderly check of the radio to find what's wrong with it? I would like to be able to bring it back to life. Thank you, -William

26th Mar 2017, 2:37 am	#2
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Roberts RIC 2 not working What do you have available, in terms of equipment? A soldering iron and a multimeter are pretty much essential. (Get simple ones to begin with; you can upgrade later.) Check for audio at the clockwise end of the volume control potentiometer, using an oscilloscope or audio amplifier. That will eliminate half of the circuit -- either the RF / IF stages, or the audio stages -- in one go ..... __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

26th Mar 2017, 3:24 am	#3
WilliamTK1974 Tetrode Join Date: Feb 2013 Location: Chattanooga, Tennessee, USA Posts: 59	Re: Roberts RIC 2 not working I do have soldering iron and multimeter, as well as knowing how to use them, but that's pretty well all I have at this time.

26th Mar 2017, 4:14 am	#4
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Roberts RIC 2 not working You could use a set of powered computer speakers, or an amplifier, or almost anything with an AUX IN and a speaker, to listen for a signal at the volume control. __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

26th Mar 2017, 11:49 am	#5
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,987	Re: Roberts RIC 2 not working You have already cleaned the switch, the other part worth doing is the Earphone socket switch it is a weak point. John.

26th Mar 2017, 12:00 pm	#6
mhennessy Dekatron Join Date: Jul 2007 Location: Evesham, Worcestershire, UK. Posts: 4,244	Re: Roberts RIC 2 not working I've found these sets to be very reliable indeed, and what problems I have had were caused by tin whiskers in the output transistors. To quickly test for this, temporarily unclip them from the heat sink clip so the cases are no longer connected to the chassis. Of course, this set has one of those notoriously unreliable earpiece sockets. So if there's absolutely nothing at all from the loudspeaker - not even a click at power-up - then that's a good place to start. You can bridge the contact to test, and often a good dose of switch cleaner and a gentle wiggle with a tooth pick or similar can sort them out. Replacements are available from Partridge Electronics. Edit: Posts crossed...

5th Apr 2017, 3:56 am	#7
WilliamTK1974 Tetrode Join Date: Feb 2013 Location: Chattanooga, Tennessee, USA Posts: 59	Re: Roberts RIC 2 not working I'm not even getting a pop from the speaker when I switch it on. I bought a PP9 battery to simplify things a bit. It tests quite good, so the set should get power. Is the mains socket in the rear of the radio a potential trouble spot? Mine appears quite corroded. Also, I inserted the tip of a metal screwdriver in between the two contacts of the adaptor socket. Some crackling ensued from the speaker, and I was able to tune in a few stations. Sound was robust but rather crackly, and reception less than ideal, but that could be due to the proximity of my computer and some other noisy items. Thank you, -William

5th Apr 2017, 7:56 am	#8
wireless_john Heptode Join Date: Apr 2011 Location: Gosport, Hampshire, UK. Posts: 605	Re: Roberts RIC 2 not working That's a point. Is there a switch on the mains socket that disconnects the battery when a plug is pushed in - and reconnect it when unplugged? I have a Grundig Hit Boy that has one. If so, it may not be reconnecting the battery. Here's another thread on the same subject: https://www.vintage-radio.net/forum/...ad.php?t=77521 John __________________ GQRP Club 4704 - BVWS Member Last edited by wireless_john; 5th Apr 2017 at 8:06 am. Reason: typo

6th Apr 2017, 4:08 pm	#10
WilliamTK1974 Tetrode Join Date: Feb 2013 Location: Chattanooga, Tennessee, USA Posts: 59	Re: Roberts RIC 2 not working The radio is back to life and running hum-free with the PP9 battery. Thanks to those who helped out with this.