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Radio Bush RG34 Radiogram (or Making a big ol bush look pretty again)

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Anonymous
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I managed to pick myself up a lovely old Bush RG34 radiogram fitted with a Garrard RC80M deck earlier in the month. With apologies to those member who may have read this article elsewhere (albeit in its toned down more serious tone). I intend to run the full ongoing story of the Big Bush and it is ongoing.

The turntable is what interested me in the first place as my other passion is building one off record turntables. I wanted to sort this to play my records or to repair/lightly restore it to play 78's. If I went down the records route then it would have meant the dismantling of the radiogram and losing the auto-change mechanism and the tonearm of the Garrard. It seemed to me to be a crime to pull apart this lovely old girl just to get a motor and platter to put into a new body. The decision was made to do the old lady up.
I had taken a couple of days off to use up the annual holiday time so I decided to brave the rain, head on down the shed and take a look at the wiring. It seems as though the turntable is wired directly into the power supply so I made up a lead and pressed on, nothing ventured and all that.
I'm jumping ahead of myself. Before I reached the point of needing power I had an inspection and clean to do.
I carefully checked the insides of the box and worked out that the deck was held on with four bolts into four sprung nuts (did Audi have anything to do with the design? "Four Sprung Technuts" geddit? badoom tish)
I snipped the two wires into the tonearm and disconnected the power wire. This is a lovely piece of old school design making working on these things a joy. It's a Bakelite plug thingie into which the power lead connects using two brass bolts. It's like wiring a plug which I guess is what it is.

With the deck completely free it was back to the kitchen table for me. The shed was bloomin freezing and the rain was lashing down. Even the dog hadn't come down the garden with me.

The wife was out with our eldest checking out a university she might want to attend and our youngest was on the interweb, twitching or something so the kitchen table was all mine. Now I'm not silly I know that grease and cobwebs and fluff and dirt do not mix well with my wife’s lovely clean oak dining table so I made sure I covered it with a sheet of newspaper and a couple of tea towels from the drawer. Who says I don’t think ahead, eh.

The turntable was carefully placed on the newspaper and a few photo’s of how it all lays out were taken. I’d like to say this was entirely for you guys as I know you like to see dirty piccies but it was all to document where everything sits. This for me to reference later when it all goes a little pear shaped and I haven’t got a clue where all the meccano pieces go as I put it all back together again.

This is what I had to play with:

I jumped in and started the clean. Degreaser, toothbrush, cloths, a little metal polish some cotton wool bud on a stick thingies, everything I needed.
I had taken out the motor as this was very dirty:

But after a few hours of patient time and effort I was happy with the result.


It was at this point that I started wondering about the electrics. You know how it is you worked hard and now you want to play. I knew that for now there would be no music but I wanted to know if the mechanics still worked. So having posted a question on a record player collectors forum , waited for oooo it must have been at least five minutes (ok, ok I had a ciggie break) I went off down to the shed did my checks and made a power lead up.

I plugged the old lady in and clicked the button. The big grin soon disappeared from my face as the platter moved about an inch before stopping. Absolutely nothing else happened. Hmmm this needs to be investigated further. I have learnt that this sort of thing is to be expected and if there is one piece of advice that I would give to any budding novice like me it would be:
Do not expect it to work. Do not think that giving it a wipe over and making it look all clean and tidy will make it go. It will not! There are years of crap and dried goo and fluff and hairs that have to be cleared out in order to get the parts to work freely. There will be worn out bits, broken bits, decayed bits which will have to be replaced. Be patient.
This is where the WD40 comes in. A liberal spray into all the cogs and wheels and other areas followed by a careful but firm turning of the main cog started getting things moving and for the first time I could see how the hundreds of different parts all linked together to make the cycle of events happen. It was like the Lion King all over again (The Lion King – Circle of life, Geddit? Oh man I’m killing myself here with these nuggets)
A little while more of spraying, turning and freeing up the parts and it was all moving smoothly once again. I plugged her in (oh yes I had unplugged, I am not going to get zapped again. Piece of advice number two: Learn from your mistakes!) and clicked over the switch. The platter started moving in total silence, the size checking arm swung across and the tonearm raised, it sensed no record was in place and swung majestically back with the tonearm returning to its rest. The start lever clicked back into its stop position and the platter came to a standstill.
My screams of delight were shriller than the fireworks being set off all weekend, the cat ran upstairs and hid under the bed and the dog went as crazy as I felt, running around the room barking at anything and everything. It worked.
I have to say that having gotten it working I was happy but this in itself was just the beginning. There were still a number of hurdles to get over. Speed adjustment, positioning of the tonearm on the edge of a record, pulleys gripping onto worn out rubber rings. All things that needed to be sorted out. That was Sundays fun for now it was jubilation that I had managed to get another of these lovely old decks resurrected and working. It, for me, is such a buzz and if anyone is thinking should I have a go at doing this then I can highly recommend getting hold of one of these lovely old Garrards and having a go.

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Topic starter Posted : 20/11/2012 3:39 pm
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Anonymous
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I'd spent a bit of time down the shed taking out the Bush radio/amplifier and speaker. Yup only one, as its a mono setup.

I thought the Garrard was a little bit grubby but it was nothing compared to the Bush this was absolutely filthy.

Attached are a few pics after I gave it a bit of a clean. You know them Karcher pressure washers do a good job and get things done real quick. Using rags, a toothbrush, various cleaning/degreasing products, the wifes hoover and loads of elbow grease however takes a damn site longer.

It appears that there is a valve missing but I have found me the correct one to replace it although I have been advised that this isn't required because a fix is in place. The valve will be there if I ever want to revert to original.

The insides however are an unknown to me. I have no idea what is what, what is good and what needs replacing, what needs "re-capping" and what re-capping even means. Some of these little beggers hold onto electrickery and they can and will kill me.

Now this is the point in time where I could do with someone local to me shouting out and inviting me to bring it over to explain and learn me about valve technology. Anybody?

I will find out. It's no good me keep getting hold of these things just to give them a bit of a clean but not get them working. oh and I have plans, big plans I want to build a radio out of bits, I want to build a valve amplifier, no wait I want to build two so that I can bi-amp my sound system, I want, I want.....

Hmm starting to sound a little bit like Brain there.

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Topic starter Posted : 20/11/2012 3:57 pm
Anonymous
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Hi Squiffything,

I like these early Garrard record decks, I did a RC60 about a year ago. They are very well made and pretty much bomb proof.

I started with mine by putting the whole mechanism in the dishwasher and gave it a good clean as it was caked in years of fluff and congealed oil (best to do this while your wife's out :) ). After a good dry I stripped it down to its last nut and bolt. Cleaned and polished each bit and then reassembled. and lubricated with oil and grease.

You may find that your mechanism starts to seize up again as the WD40 only has limited lubricating properties and is really a water displacer and rust inhibitor. It will have thinned the existing grease and oil but this will start to congeal again. I found Singer sewing machine oil is ideal for the bearings and a light smear of grease for the gears and levers.

Best wishes,
Keith

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Topic starter Posted : 20/11/2012 8:00 pm
Anonymous
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Hi Keith

Wd40 was kept clear of the bearings and light oil used to lubricate. It'll only be used for 78's as the arm is too heavy for vinyl.

It is a lovely piece of machinery though.

Now it's getting the replacement caps to change out the waxies that are needed. I've had some great pointers from one of the guys on here so when I get the bits I'll make a start.

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Topic starter Posted : 21/11/2012 12:26 am
ianj
 ianj
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The Bush rg 54 with the Garrard rc80 is quite a nice piece of kit,certainly a cut above.

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Posted : 21/11/2012 2:38 am
Anonymous
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Thanks Ian

She certainly is a grand ol Lady

Her top leaves alot to be desired but I will be stripping her back to bare and re-covering her. I haven't decided yet on how I will do this yet but a bit of work ahead of me.

Inside the top she looks lovely.

These were the original photo's taken when I brought her home so she looks even nicer after the Garrard was cleaned and fettled and the inner wood has had a wipe over with the wifes Pledge.

The wiring needs renewing, lots of old brittle sections and plenty where the covering has broken away leaving bare open bits. One of the ickle bulbs has blown but that shouldn't be too bad to find a replacement. There's one piece of the wooden frame at the bottom and to the rear that has a little bit of worm that needs treating or replacing. I'm not sure if its active still but I'll squirt some stuff on it and then decide later which way I'll go with this. The back board is like new with lovely sharp printing and no dents/warps etc although one or two of the holes into which the screws screw into are missing from the frame. I'm not sure if these are still available and I certainly do not have the lathe skills or lathe to fabricate them. I will carry out a search in time to see if I can find them.

So as you can see a few jobs to keep me busy and I've still got to learn all about valves and capacitors and resistors and stuff. :)

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Topic starter Posted : 21/11/2012 11:06 am
Anonymous
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.

I see quite a few waxy capacitors in that amp - don't try and use it till they've been changed!

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Topic starter Posted : 24/11/2012 1:11 pm
Anonymous
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Hi Ben, yup I've got that in hand. It's the next job to do when I get round to sorting the replacements.

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Topic starter Posted : 24/11/2012 2:29 pm
Terry
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... It appears that there is a valve missing but I have found me the correct one to replace it although I have been advised that this isn't required because a fix is in place. The valve will be there if I ever want to revert to original ...

The 'fix' is clearly visible in the picture - it is a silicon rectifier connected from the valve rectifier valveholder to, presumably, the smoothing cap (only one end visible, so this bit is guesswork).

If this is the case, the HT level may be considerably higher than as designed using the valve rectifier. Also, a much higher voltage - which may exceed the capacitor rating - will be present immediately at switch on when there is no load. This doesn't happen as designed because all the valves, including the rectifier, warm up together, matching demand to supply.

Reverting to the original valve design and removing the diode would be a good idea ...

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Posted : 24/11/2012 2:33 pm
Anonymous
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I've had to go as high as 270 Ohms when replacing a valve rectifier with Silicon.

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Topic starter Posted : 24/11/2012 2:48 pm
Anonymous
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Hopefully a little better view

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Topic starter Posted : 24/11/2012 3:10 pm
valvekits
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I noticed the rectifier as well it looks like the BY127 variety. What struck me as odd though, assuming there should be an EZ80/81 in that position, why is there nothing connected to the heater pins. It looks as though they have never seen solder before. If you were just short of a valve, the diode would be a quick fix but it wouldn't be necessary to remove the heater wiring.

Eddie

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Posted : 24/11/2012 7:24 pm
Refugee
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It looks like an 8 pin base to me.
I have a set with just such a base in the power supply and it has an EZ40 in there.
I looked at the top view of the chassis and the pip would be it the top in the underside view and so would the heaters be at the top.
I think it may be half wave with both anodes connected in parallel and that is why there is only one diode. It may also have been a half wave right from the start.
It is i am pretty sure it is 8 pin with a pip no matter what else.

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Posted : 24/11/2012 11:21 pm
valvekits
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Yes you are correct Refugee I had been looking at the chopped off picture, I missed the updated pic right above my post.

Eddie

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Posted : 24/11/2012 11:58 pm
Andrewausfa
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Should be a UY41 in there.

Andrew

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Posted : 25/11/2012 12:32 am
Anonymous
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I'm told the black bullet shaped thing and the green tube thing are the fix for the missing uy41 and if the valve is replaced both would need removing, the black bullet is the silicon rectifier? What would the green thing be?

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Topic starter Posted : 25/11/2012 12:57 am
Refugee
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It is a dropper resistor that replaces the heater in the valve.
There will be a wire that may also have been chopped between the point the resistor is soldered to and the valve holder.
The wire the diode replaces would also have to go back too.
I was court on the "hop" by there being a transformer in the chassis and assumed it was regular AC only set with a full wave E series rectifier in there.
Is it a series chain running from a transformer?

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Posted : 25/11/2012 2:41 am
Terry
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It is definitely a series heater chain - a previous picture shows U series valves and an N142 (equivalent to UL41).

The rectifier will be a UY41.

Note that this is taken from a multi-lingual data sheet. In English we differentiate between the filament of a directly heated valve and the heater of an indirectly heated valve (with separate cathode) and a UK data sheet would show h - h in place of f- f. There is no difference as far as the valve is concerned!

The last picture is on a rather small scale and indistinct - a clear blown-up picture of the area under discussion would have been useful - so I hope this translation is accurate:

I can't make out where point 'X' is, although I assume it is a tag on the transformer.

To reinstate the valve, remove the two components shown - the silcon diode and the wirewound resistor, taking careful note of where point 'X' is and add two new wires as shown below:

Then replace the valve.

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Posted : 25/11/2012 1:59 pm
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Today has been a good day. I had a visitor who has taught me more in his time here than I could ever have possibly learnt in a month os Sundays. Thank you Andrew it was great meeting you and to get the Bush running and receiving radio broadcasts was fantastic. Andrew won the reward of the Leak and I hope you get full enjoyment out of it. Let us know how you get on with the mini challenge set to you.

The day started with a run down on my limitations both with knowledge and equipment. I'm pleased to say that he had brought with him a selection of gadgets and gizmos for me to learn about and to play with :). I definitely need a decent meter and a more powerful soldering iron so my Chimbo list has been prepared.

We had a quick look over my home made record players and the selection of projects that await me in the shed. He liked the look of the Philips and seemed impressed with how I'd got it looking so far but we agreed the bush should be the one we worked on today.

We checked her over with the meter and it was good to know what it could do and how to carry out the checks we did. I learnt how to run through the circuit diagram and how to sort out the components that might give trouble. We started on sorting out the crumbling wiring and changed out a lot of the old ruined sections. We then sorted out the 'fix' that had been done and replaced the missing valve removing the green resitor and the little black diode. And adding the missing wiring. She now had a full compliment of valves.

We then went on a replacement run of some of the waxies that would definitely be at the end of their time. Nearly sixty years old they had done their job. Andrew also sorted me out the remaining replacements to get round to replacing as a coverall job in my own time.

We connected her up via the lamp limiter and fired her up. The bulb lit and then dropped to barely a glow as the valves all let out their individual light. this to me was brilliant and what i had been waiting for from the moment i had brought her home. A little tuning on MW and we found the footie on Radio Five. The tiny little bulbs we had replaced all lit up. Andrew checked her over, the valves were warming up nicely and the big silver cap was cool and stayed that way. It wasn't perfect to him but to me having my first valve radio working was a true delight. I could truly understand why you guys put so much time into getting these lovely old things up and running.

We disconnected and squirted some contact cleaner into the pots to give them better contacts and fired her up again without the limiter. Much louder and more channels on all three bands. Andrew said that a decent aerial would improve that more which I will sort out when I refit the chassis back into the case.

As you will appreciate the above is an abridged version of the days events. There was a lot more testing and tweaking going on, the soldering was slow as I was involved in it and the running through the diagram took its time. But my tutor was patient and very informative and as a good teacher should be, let me work things through confirming or correcting as required.

Andrew thank you so much for the time you have given, your patience, your bits and bobs to get the old girl running and your enthusiasm and encouragement towards me meaning that I will dive headlong into this great hobby.

Now where's that circuit diagram for the stereo valve amp I want to build? :)

I will post up some pictures of the progress so far when I get to the computer tomorrow.

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Topic starter Posted : 26/11/2012 1:41 am
Refugee
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It was a bit of a long way for me.
I am often quite good at doing awkward jobs.

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Posted : 26/11/2012 2:08 am
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