BSR GU4 help required - UK Vintage Radio Repair and Restoration Discussion Forum

hayerjoe · 11th Apr 2021, 4:23 am

Hello again

I've just picked up an old Australian Kreisler radiogram and have a few questions I hope you can help with (see photos)

1) is this a BSR GU4 record player? looking at the BSR deck recognition page makes me think it is, but it comes out of a radiogram that has stamped in it (wait for it...) December 1947! which I think is a good 4 years before the GU4 was released. Was there a GU3?

2) radiogram itself is fairly immaculate internally for something from 1947, but it has no model name or number anywhere. Does anyone know what it is?

3) this is embarrassing but i can't get the cartridge out. Don't want to force anything, does anyone know how to do it? if there is a cartridge number/ident on it, I can't find it, but it does say BSR

FYI it tracks at 13g+. this is not a question but thought you'd like to know it. Already with a bit of blutack and some washers I can get that number down easily to a positively lightweight 6g, so whatever cartridge I fit I hope i can stop it digging my grooves in all the wrong ways

Look forward to your replies

Joe

wd40addict · 11th Apr 2021, 8:45 am

Microgroove records (33 & 45RPM) didn't exist in 1947 so deck is definitely later. Web sources suggest the GU4 is from 1951.

Edward Huggins · 11th Apr 2021, 9:49 am

Yes, this is BSR GU4, but also known as a BSR "Regent". It was introduced in early 1952 - but earlier versions of it used in the Decca "Deccalian. It's built like a battleship and with its heavy pressed steel 10" platter gives a good account of itself. The weakness is the heavy arm which has no tracking weight adjustment. You are doing the right thing by loading the exteme rear end of the tone arm with weights. The cartridge is the BSR TC4 "groove digger", their first LP/78 turnover type. If you press the turnover knob towards the rear end of the arm you might then see how it can be removed.

hayerjoe · 11th Apr 2021, 10:05 am

Quote:

Originally Posted by wd40addict

Microgroove records (33 & 45RPM) didn't exist in 1947 so deck is definitely later. Web sources suggest the GU4 is from 1951.

Yes that is strange, I know things moved slower "in the past" but would they really have veneer stamped 1947 lying around unused for 4+ years? possibly i guess?

julie_m · 11th Apr 2021, 10:33 am

It's possible the radiogram could have been built in 1947 with a 78 rpm-only deck, and later upgraded to play microgroove records.

Techman · 11th Apr 2021, 12:49 pm

I would say definitely a replacement deck - it was very common back then and it was certainly something I did myself even in the 70s to replace old single speed 78 rpm decks. The only odd thing is that the head of the tone arms on those particular decks is usually what I call 'boat shaped' and that one isn't, but that may be because it was made for the Australian market, so has a different styling. That cartridge will definitely damage modern records, but if it still works (perhaps unlikely) then why not leave it in place and just use it to play 78s and vintage 50s/60s seven inch 45s. A player like that shouldn't really be used to play any valuable records on if you're bothered about keeping their future value and condition.

hayerjoe · 11th Apr 2021, 1:03 pm

OK, would seem sensible that the deck was replaced, I bet the BSR cut out and mounting points would be the same just 3-4 years later

I really have no 78s and a tiny smattering of mono records so I will definitely be upgrading the cartridge to stereo compatibility (though still mono of course). The fun is getting these things functional again rather than truly practical I mean even with a modern cartridge it's not gonna be good for records longterm, it's not very sophisticated and light-touch. With that said I still don't know how to safely get the existing cartridge out, any ideas?

thanks everyone

hayerjoe · 11th Apr 2021, 1:06 pm

oh I should have said, old cartridge does still work, and that was on half power via my lamp limiter! Things were built to last in those days

Techman · 11th Apr 2021, 1:30 pm

Quote:

Originally Posted by hayerjoe

Things were built to last in those days

Well yes and no when it comes to cartridges.

Crystal cartridges of the time absorbed moisture from the atmosphere and dissolved internally, but it could be that where you are in the world it's lived an easier life and has survived. I'm not sure what that cartridge is - there may be a make and type number on it. There looks to be a couple of little caps covering screws on top of the pickup head. Sometimes there's a push and turn arrangement on the front 'turn-over', but try those two hidden screw heads first.

Another possible oddity is that the cartridge could be an early magnetic type, like the TOM 1 and 2, but I doubt it is. If it is, then you'll have trouble with impedance matching any replacement.

Techman · 11th Apr 2021, 3:28 pm

Quote:

Originally Posted by Edward Huggins

If you press the turnover knob towards the rear end of the arm you might then see how it can be removed.

Yes, it's quite likely that if the OP removes those caps on the top of the head that there may just be a captive nut underneath each one, or if there's a screw head, then it may just turn without undoing due to nuts revolving beneath. When I mentioned the 'push and turn' arrangement, I seem to think that it may be a case of holding the body of the cartridge while pushing and turning the front turnover knob, thus releasing the cartridge from its mounting bracket, but it's been so long since I did one that I can't remember the exact procedure, although I bet there's a description of it on-line somewhere if you search hard enough. Someone may come along eventually who remembers the exact procedure, although you'll probably work it out for yourself if you study it long and hard enough.

Audio1950 · 11th Apr 2021, 5:21 pm

Quote:

Originally Posted by Techman

When I mentioned the 'push and turn' arrangement, I seem to think that it may be a case of holding the body of the cartridge while pushing and turning the front turnover knob, thus releasing the cartridge from its mounting bracket

Do this, and whilst holding the knob and the cartridge together, push out the little pin that goes through the knob. The knob and spring will then come off the front, and the cartridge withdrawn. The bracket will then be revealed, and should have two screws that go into the nuts that are concealed on the top of the arm.

Barry

hayerjoe · 12th Apr 2021, 7:03 am

thank you everyone

I managed to get the cartridge off - see photos. There is a small but long screw that goes through the cartridge body and into the shaft of the knob used to turn the cartridge. With this removed, you can pull the knob out and the cartridge is then easy to remove. BUT beware, at the other end of the cartridge is a tiny spring and plunger, it's not secured in any way and is therefore easy to lose.

the cartridge has no product number on it anywhere, not very helpful, and it with its clip weighs a whopping 14.4g!

Edward Huggins · 12th Apr 2021, 9:11 am

I can assure you that this is a BSR TC4 and it's still possible to source both LP and 78 styli for ths. It generated enough output to load a single UL41 in the very early Dansettes.

Audio1950 · 12th Apr 2021, 3:31 pm

It's a BSR TC4.

Barry

Techman · 12th Apr 2021, 5:56 pm

The weight of that cartridge isn't unusual and would normally be counterbalanced at the rear of the arm, but I don't think there's an adjustment on that particular deck, although I think the OP is improvising with some stuck on bits of metal. Remember not to get ANY heat from a soldering iron anywhere near the electrical connections to either that or a replacement cartridge.

Ekcoman · 12th Apr 2021, 8:16 pm

Quote:

Originally Posted by hayerjoe

oh I should have said, old cartridge does still work, and that was on half power via my lamp limiter! Things were built to last in those days

Definitely built to last and here's mine still giving good sound and output but definitely not for your treasured vinyl.

hayerjoe · 13th Apr 2021, 9:08 am

So it is a TC4, thanks for identifying it.

I will be careful soldering the new cartridge in. FYI see attached the TC4 has female connectors which was a surprise to me when I pulled them out

Also you were all correct that the GU4 was retrofitted See photo, underneath that rather tatty looking board with the the 3 supports for the GU4 is a nice walnut cut out for the previous record player

Thanks for all your help

11th Apr 2021, 4:23 am	#1
hayerjoe Hexode Join Date: Oct 2020 Location: Bridgewater, Tasmania, Australia Posts: 483	BSR GU4 help required Hello again I've just picked up an old Australian Kreisler radiogram and have a few questions I hope you can help with (see photos) 1) is this a BSR GU4 record player? looking at the BSR deck recognition page makes me think it is, but it comes out of a radiogram that has stamped in it (wait for it...) December 1947! which I think is a good 4 years before the GU4 was released. Was there a GU3? 2) radiogram itself is fairly immaculate internally for something from 1947, but it has no model name or number anywhere. Does anyone know what it is? 3) this is embarrassing but i can't get the cartridge out. Don't want to force anything, does anyone know how to do it? if there is a cartridge number/ident on it, I can't find it, but it does say BSR FYI it tracks at 13g+. this is not a question but thought you'd like to know it. Already with a bit of blutack and some washers I can get that number down easily to a positively lightweight 6g, so whatever cartridge I fit I hope i can stop it digging my grooves in all the wrong ways Look forward to your replies Joe Attached Thumbnails

11th Apr 2021, 8:45 am	#2
wd40addict Octode Join Date: May 2009 Location: Stevenage, Herts. UK. Posts: 1,518	Re: Bsr GU4 help required Microgroove records (33 & 45RPM) didn't exist in 1947 so deck is definitely later. Web sources suggest the GU4 is from 1951.

11th Apr 2021, 9:49 am	#3
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,336	Re: Bsr GU4 help required Yes, this is BSR GU4, but also known as a BSR "Regent". It was introduced in early 1952 - but earlier versions of it used in the Decca "Deccalian. It's built like a battleship and with its heavy pressed steel 10" platter gives a good account of itself. The weakness is the heavy arm which has no tracking weight adjustment. You are doing the right thing by loading the exteme rear end of the tone arm with weights. The cartridge is the BSR TC4 "groove digger", their first LP/78 turnover type. If you press the turnover knob towards the rear end of the arm you might then see how it can be removed. __________________ Edward.

11th Apr 2021, 10:33 am	#5
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Bsr GU4 help required It's possible the radiogram could have been built in 1947 with a 78 rpm-only deck, and later upgraded to play microgroove records. __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

11th Apr 2021, 12:49 pm	#6
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: BSR GU4 help required I would say definitely a replacement deck - it was very common back then and it was certainly something I did myself even in the 70s to replace old single speed 78 rpm decks. The only odd thing is that the head of the tone arms on those particular decks is usually what I call 'boat shaped' and that one isn't, but that may be because it was made for the Australian market, so has a different styling. That cartridge will definitely damage modern records, but if it still works (perhaps unlikely) then why not leave it in place and just use it to play 78s and vintage 50s/60s seven inch 45s. A player like that shouldn't really be used to play any valuable records on if you're bothered about keeping their future value and condition.

11th Apr 2021, 1:03 pm	#7
hayerjoe Hexode Join Date: Oct 2020 Location: Bridgewater, Tasmania, Australia Posts: 483	Re: BSR GU4 help required OK, would seem sensible that the deck was replaced, I bet the BSR cut out and mounting points would be the same just 3-4 years later I really have no 78s and a tiny smattering of mono records so I will definitely be upgrading the cartridge to stereo compatibility (though still mono of course). The fun is getting these things functional again rather than truly practical I mean even with a modern cartridge it's not gonna be good for records longterm, it's not very sophisticated and light-touch. With that said I still don't know how to safely get the existing cartridge out, any ideas? thanks everyone

11th Apr 2021, 1:06 pm	#8
hayerjoe Hexode Join Date: Oct 2020 Location: Bridgewater, Tasmania, Australia Posts: 483	Re: BSR GU4 help required oh I should have said, old cartridge does still work, and that was on half power via my lamp limiter! Things were built to last in those days

12th Apr 2021, 7:03 am	#12
hayerjoe Hexode Join Date: Oct 2020 Location: Bridgewater, Tasmania, Australia Posts: 483	Re: BSR GU4 help required thank you everyone I managed to get the cartridge off - see photos. There is a small but long screw that goes through the cartridge body and into the shaft of the knob used to turn the cartridge. With this removed, you can pull the knob out and the cartridge is then easy to remove. BUT beware, at the other end of the cartridge is a tiny spring and plunger, it's not secured in any way and is therefore easy to lose. the cartridge has no product number on it anywhere, not very helpful, and it with its clip weighs a whopping 14.4g! Attached Thumbnails

12th Apr 2021, 9:11 am	#13
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,336	Re: BSR GU4 help required I can assure you that this is a BSR TC4 and it's still possible to source both LP and 78 styli for ths. It generated enough output to load a single UL41 in the very early Dansettes. __________________ Edward.

12th Apr 2021, 3:31 pm	#14
Audio1950 Dekatron Join Date: Nov 2008 Location: Whittlesey, near Peterborough, Cambridgeshire, UK. Posts: 3,763	Re: BSR GU4 help required It's a BSR TC4. Barry

12th Apr 2021, 5:56 pm	#15
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: BSR GU4 help required The weight of that cartridge isn't unusual and would normally be counterbalanced at the rear of the arm, but I don't think there's an adjustment on that particular deck, although I think the OP is improvising with some stuck on bits of metal. Remember not to get ANY heat from a soldering iron anywhere near the electrical connections to either that or a replacement cartridge.

13th Apr 2021, 9:08 am	#17
hayerjoe Hexode Join Date: Oct 2020 Location: Bridgewater, Tasmania, Australia Posts: 483	Re: BSR GU4 help required So it is a TC4, thanks for identifying it. I will be careful soldering the new cartridge in. FYI see attached the TC4 has female connectors which was a surprise to me when I pulled them out Also you were all correct that the GU4 was retrofitted See photo, underneath that rather tatty looking board with the the 3 supports for the GU4 is a nice walnut cut out for the previous record player Thanks for all your help Attached Thumbnails