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Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
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7th Dec 2022, 12:40 pm | #1 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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RGD 516 Receiver.
Hi, picked up this radio, it had been worked on before and maybe for sale because seller did not want to continue.
The cabinet was in great condition and just needed the two thin wood things top and bottom of the grill, bringing back to bare and oiling,(the good bit). I have sorted out all the bad crackling and popping that was going on but still have some issues with the selectivity and tone controls. Changing the selectivity switch off it's first position reduces the volume a lot ? The reason for the post however is the wafer switch responsible for the P.U. SW1 is damaged and will not select Has anyone tried to repair this type of switch before and can pass on any tips before I take it apart with some trepidation, on the picture you can see a piece that has become detached and i am assuming it is the culprit. fingers crossed someone can help. Rob. |
7th Dec 2022, 2:07 pm | #2 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,362
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Re: RGD 516 Receiver.
Hi Rob, you might be able to repair the switch but first you need to work out what is causing it to jam. Take detailed photos and/or make sketches as to where the wires go before de-soldering them, then remove the switch. By undoing the nuts and bolts you should be able to separate the wafers and sort out the problem. Looking at the circuit (Trader #598 is easier to understand so component numbers here correspond to that) the switch assembly is a rotary wafer and you need 2-pole 3-way as a replacement. You can usually find them on eBay and elsewhere although new wafers from RS Components tend to be pricey. First make sure the replacement switch is physically small enough to fit the space envelope and the shaft diameter is right. You might need to alter the length of the knob shaft. Working out the connections for a new switch needs a bit of patience since the tag configuration will probably look different: One fixed pole goes to R16, the V3 grid 2 feed (and also to one of the 1st IFT trimmer C43) and the corresponding 3 tags need to be connected as follows: position 1 tag connect to bottom of L20 (this is S41), position 2 tag bridge to position 3 tag and connect to the bottom of L21 (this is S40). The second pole goes to the smoothed HT line and the "hot" end of R23. The corresponding tags are: position 1 tag no connection, position 2 tag goes to junction R23/R24 (this is S42), and finally position 3 tag goes to C23 (this is S43). Hope that helps! I've now got a horrible feeling I've just described how to replace the wrong switch..... Reading your post again it looks like the selectivity switch is OK. The P.U. switch looks like it is one of the positions on the wavechange switch. The same principles as described above apply but removing the wavechange switch assembly is probably a bad idea unless you are very brave. Examine closely in-situ first and try to spot why the P.U. position will not operate. If you can't release the jam it might be simpler to hard wire the P.U. socket onto the volume control and add a simple single pole switch at the back to break the radio signal input. Jerry
Last edited by cathoderay57; 7th Dec 2022 at 2:22 pm. |
7th Dec 2022, 2:16 pm | #3 |
Dekatron
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
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Re: RGD 516 Receiver.
Get the switch wafers out of the radio then you can properly assess the damage. Take lots of pictures before desoldering!
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7th Dec 2022, 5:00 pm | #4 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
hi, thanks for replies, i have put an arrow on the pic to show what part that is adrift, i have the schematics, problem as i see it is that if i cannot repair the wafer that the long control bar is flat not round.
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7th Dec 2022, 8:58 pm | #5 |
Dekatron
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,171
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Re: RGD 516 Receiver.
Hi Rob, flat shaft switches were not unusual in these sets. If all else fails and you are not in a hurry I may be able to find some similar wafers if you can post detailed pics of the dead ones
Note that some of these switches had an earthing wafer that shorted all b ut the active contact to ground Ed |
7th Dec 2022, 9:59 pm | #6 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
Hi Ed, i am going to get it out tomorrow pm and i will post some pictures.
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8th Dec 2022, 4:12 pm | #7 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
hi, here are the pics, as you can see previously a repair had been done to the damaged centre piece by super gluing the small round disc with the oblong hole to the centre broken bit that rotates the switch, all the switches work when you turn the centre with a screwdriver blade,i'll ponder on.
Rob. |
8th Dec 2022, 6:10 pm | #8 |
Dekatron
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
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Re: RGD 516 Receiver.
An aggressive clean is required to get rid of any grease/oils, I use Viakal bathroom cleaner. The broken section seems to correspond with the 3 vertical holes on the other side so I would wait till dry then stick the repair disk back on with araldite.
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8th Dec 2022, 8:26 pm | #9 |
Dekatron
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,171
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Re: RGD 516 Receiver.
Hi Rob, that one looks a little strange as itwould appear to be able to accept both "D" and flat shafts.
Let me know how you get on as I certainly have wafers like that for flat shafts Ed |
8th Dec 2022, 9:00 pm | #10 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
ed, pm sent.
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8th Dec 2022, 9:15 pm | #11 |
Dekatron
Join Date: Mar 2005
Location: Gateshead, Tyne and Wear, UK.
Posts: 7,444
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Re: RGD 516 Receiver.
When I acquired my RGD 516 in 1982 one of the first jobs to do the set was fit an on-off and selectivity switch. It was missing. Components used to make a substitute component were sourced from RS Components Ltd.
In those times RS made available an on-off switch designed to work with multi-way wafer switches. The mains switch was made by Lorlin. I believe the switch shown in the attachment is no longer made. However, Lorlin make a switch which might be suitable for similar applications. https://lorlinelectronics.co.uk/product/ms2000-mains DFWB. |
15th Feb 2023, 5:04 pm | #12 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
just when i thought i had it finished,put it back in the cabinet the mains transformer started smoking, checked and it was drawing 6.5 !!! amps with all secondaries disconnected, there was evidence that it had got hot when i bought it but it had been behaving itself so it looks like a lot of work for nothing unless i pod out to have it rewound, i'll think on and contact Ed.
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29th May 2023, 9:20 am | #13 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
decided to get Ed to rewind the transformer, great job done and when fitted virtually zero level of hum, the sound from this 80+ year old radio is also very surprising, added bluetooth to the gram input and a little preamp to equalise the volume.
i just glued the wafer switch centre back on and so far so good. still trying though to remove the few light patches you can see along the front top edge. It is tuned to gold radio which seems to be the right sound for my old radio's,but you can also get what is on LW and shortwave stations but that was on a long wire from my shed on to the washing line. |
29th May 2023, 1:15 pm | #14 |
Nonode
Join Date: Oct 2017
Location: Bristol, UK.
Posts: 2,362
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Re: RGD 516 Receiver.
Great result, well done!
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30th May 2023, 5:37 pm | #15 |
Dekatron
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,171
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Re: RGD 516 Receiver.
Hi Rob, good to hear it is running nicely. A god solid set
Not managed to find my spare wafers yet, but if your repair fails give me a call Ed |
2nd Jun 2023, 7:37 pm | #16 |
Dekatron
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
Posts: 5,263
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Re: RGD 516 Receiver.
lovely!
__________________
Kevin |
4th Jun 2023, 10:53 pm | #17 |
Hexode
Join Date: Jun 2009
Location: Cheshire, UK.
Posts: 363
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Re: RGD 516 Receiver.
Very nice
Tuning indicator looks good - a TV4 I believe. Was it already in the set or did you have to get a replacement/substitute it? |
4th Jun 2023, 11:02 pm | #18 |
Dekatron
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
Posts: 5,263
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Re: RGD 516 Receiver.
catalogue entry:
__________________
Kevin |
5th Jun 2023, 9:51 am | #19 |
Pentode
Join Date: Apr 2020
Location: Derby, Derbyshire, UK.
Posts: 194
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Re: RGD 516 Receiver.
tuning indicator was already in, some work had been done before i purchased it (which i undid) the internals will not stand a lot of handling though but really after all these years it is amazing ,must have had a good home.
thanks for the add i will try and print. |