Help with Dynatron Calvacade music centre - UK Vintage Radio Repair and Restoration Discussion Forum

paullamey · 14th Jul 2018, 10:10 am

Hello!

I was given an old calvacade music centre SRX30B It's really beautiful but am aware that the record player a Goldring G101 isn't the best. It plays at inconsistent speeds, mostly a fraction slower. I had a vintage repair man come out - which was a really bad experience. He turned up at 11 at night - charged me £100 and told me, after doing some poking around, that record players in the 70s never played to true speeds. He changed the belt but i don't know if it was even the correct one.

I don't really know what to do next! Any advice would be great. I apologise for my naivety!

Thanks!

Nuvistor · 14th Jul 2018, 10:59 am

I think I would have sent him on his way turning up at 11pm.

I don’t think there is a seperate speed control so check the mechanism, motor bearings free, turntable bearing free etc. The belt needs to be the correct one, too slack it will slip, too tight will stall the motor. Make sure there is no grease or oil on any of the running surfaces.

Not sure how accurate the speed is on these decks but it should be good enough for most except the most critical. Perhaps not Goldring's finest but should perform satisfactory in the Dynatron.

Edward Huggins · 14th Jul 2018, 11:37 am

The Goldring 101 deck may not be in Gararrd 401 class, but it's more than adequate and compatible with that Dynatron of yours. Properly set up, they are as good as, or better, than the usual default Garrard SP25 series. Belts are just £1.00 for a set from which a near match might be found.
Being charged £100 really gets to me. This is yet another tale of those being ripped off by "engineers" claiming to be vintage specialists that are cashing it on the "Vinyl" boom. Recently, I heard of a person paying £130.00 for a deck lube and stylus change on an old bog standard Fidelity model. They then come to me, after they've paid out, to ask what I think? Stupid old me, I would have charged a Fiver for my time and the fitted the stylus at its actual cost.

paulsherwin · 14th Jul 2018, 11:58 am

To be fair, people doing vintage repairs as a business rather than a hobby are entitled to charge for their time in the same way as a plumber or electrician, but obviously that's no excuse for sharp practice.

It's true that cheap record players and audio systems often don't have a very accurate speed by hifi standards, though Dynatron stuff wasn't particularly low end. People coming to records for the first time may be very intolerant of pitch errors and variations, as the digital sources they're used to will be absolutely pitch perfect. Back in the day people just put up with it.

That's not to say there isn't a fault present in this case of course. The deck probably needs a stripdown and relube.

Nuvistor · 14th Jul 2018, 12:23 pm

I haven’t a problem with the £100, including travel time it could have been 2 hours. It’s the time of day for a none urgent call that I find difficult to accept.

I wouldn’t be opening the door at that time unless I knew the person.

paullamey · 14th Jul 2018, 12:49 pm

Thanks for the advice. I think the person that came round did strip it and oil / lube the parts. I just have a feeling the belt might not be the right one - or that it's that that is causing the problem.

Would someone be able to point me in the right direction for where to get some belts I could try? I've had a look online but can't find the right one where they're in stock. And £15 seems an awful lot for essentially on O ring!

Or if anyone knows anyone in the London area that is good for repairs that won't charge me £100 and turn up near midnight!

Thanks again for all your help. Appreciate it.

paulsherwin · 14th Jul 2018, 2:07 pm

Can you examine the belt which has been fitted? It should be tight enough not to slip, but not so tight so as to be significantly stretched. Turntable drive belts are usually quite long flat belts, though I don't know this deck. Belt design isn't usually very critical if the diameter is correct, particularly in this category of equipment.

You can buy an assortment of belts for next to nothing, e.g. https://www.ebay.co.uk/itm/30pcs-Sma...gAAOSwUH5aXGud but there may not be a large enough belt and they will probably be square section rather than flat.

Although you are unhappy with your repairman, he has at least dismantled and examined the unit, which is more than people commenting here have (including me). Did he have any comments to make about the problems, other than "they're all like that"?

Nuvistor · 14th Jul 2018, 2:20 pm

According to this they are a triangular belt.
https://www.musonic.co.uk/101-origin...t-p-17879.html

paulsherwin · 14th Jul 2018, 2:33 pm

It looks to me as if a flat belt of the right diameter would be absolutely fine as a replacement. Even a square belt from the cheap Chinese selection would probably be OK if it's the right size in other respects. Other sources suggest the belt is round or square section, so it probably doesn't matter much.

From the photo, it looks as if this deck has a low voltage DC motor with electronic speed control. The speed fault may be being caused by this rather than any belt problem. Other sources say it has a synchronous motor though, so the Musonic illustration may be misleading.

Nuvistor · 14th Jul 2018, 2:37 pm

Could well be a low voltage motor, I cannot find any information about it though.

Nuvistor · 14th Jul 2018, 3:07 pm

Found this page, not a lot of info but seems to be a synchronous motor.
https://www.vinylengine.com/library/goldring/g101.shtml

Edward Huggins · 14th Jul 2018, 3:07 pm

If it is just the Belt that's needed, then £15.00 is not a bad price and will be a bit more than an "O" ring. However the motor and its control circuitry may need to be eliminated as well.

jamesperrett · 15th Jul 2018, 2:08 pm

I had one of these for a while and remember changing the belt on it. The belts are fairly thin - certainly thinner than I was expecting. As I remember it, the torque from the turntable is fairly low so even something like too much tracking force could slow it down. The one I had was fitted with a Shure M75-6 cartridge which I seem to remember was set to 3g of tracking force.

Station X · 15th Jul 2018, 2:15 pm

Check the speed using a strobe disc with and without the stylus being in contact with the record?

paulsherwin · 15th Jul 2018, 2:26 pm

I think the platter edge actually has strobe markings. A traditional fluorescent light will provide a 50Hz strobe, though a compact fluorescent won't.

David G4EBT · 16th Jul 2018, 8:04 am

You can download strobe discs (for 50 Hz & 60Hz) free of charge from the vinylengine site here:

https://www.vinylengine.com/strobe-discs.shtml

Not sure if you have to be a member to download, (I'm a member), but like this forum, it's a simple process to join.

That enables you to download (and upload) manuals FOC.

Hope that might help a bit.

vidjoman · 16th Jul 2018, 9:40 am

The belt used was triangular in shape and the groove in which it runs will have a 60 degree angle cut in it, not the 90 degrees needed for a square belt. A square belt will not work as it will be pinched in the groove of the motor drive and the turntable.

Beobloke · 16th Jul 2018, 12:59 pm

As vidjoman says, this is one deck where "any old belt that looks about right" will NOT work. The pulley groove is very deep and a round, square or flat belt will ride too far out and make the deck run fast.

paulsherwin · 16th Jul 2018, 3:16 pm

Maybe that's the symptom that the OP is complaining about?

Nickthedentist · 16th Jul 2018, 3:22 pm

Just to clarify some of the above, this deck has a synchronous motor, triangular cross-section belt, very light aluminium platter with plasticy hub around which the belt runs, and has no strobe marking or means of adjusting the speed. The belt has to be just right or else it won't work satisfactorily.

I was always disappointed with the performance of mine and ended up fitting a skip-found Dual 505 in its place.

14th Jul 2018, 10:10 am	#1
paullamey Retired Dormant Member Join Date: Jul 2018 Location: London, UK. Posts: 4	Help with Dynatron Calvacade music centre Hello! I was given an old calvacade music centre SRX30B It's really beautiful but am aware that the record player a Goldring G101 isn't the best. It plays at inconsistent speeds, mostly a fraction slower. I had a vintage repair man come out - which was a really bad experience. He turned up at 11 at night - charged me £100 and told me, after doing some poking around, that record players in the 70s never played to true speeds. He changed the belt but i don't know if it was even the correct one. I don't really know what to do next! Any advice would be great. I apologise for my naivety! Thanks!

14th Jul 2018, 10:59 am	#2
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Help with Dynatron Calvacade music centre I think I would have sent him on his way turning up at 11pm. I don’t think there is a seperate speed control so check the mechanism, motor bearings free, turntable bearing free etc. The belt needs to be the correct one, too slack it will slip, too tight will stall the motor. Make sure there is no grease or oil on any of the running surfaces. Not sure how accurate the speed is on these decks but it should be good enough for most except the most critical. Perhaps not Goldring's finest but should perform satisfactory in the Dynatron. __________________ Frank

14th Jul 2018, 11:37 am	#3
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,328	Re: Help with Dynatron Calvacade music centre The Goldring 101 deck may not be in Gararrd 401 class, but it's more than adequate and compatible with that Dynatron of yours. Properly set up, they are as good as, or better, than the usual default Garrard SP25 series. Belts are just £1.00 for a set from which a near match might be found. Being charged £100 really gets to me. This is yet another tale of those being ripped off by "engineers" claiming to be vintage specialists that are cashing it on the "Vinyl" boom. Recently, I heard of a person paying £130.00 for a deck lube and stylus change on an old bog standard Fidelity model. They then come to me, after they've paid out, to ask what I think? Stupid old me, I would have charged a Fiver for my time and the fitted the stylus at its actual cost. __________________ Edward.

14th Jul 2018, 11:58 am	#4
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Help with Dynatron Calvacade music centre To be fair, people doing vintage repairs as a business rather than a hobby are entitled to charge for their time in the same way as a plumber or electrician, but obviously that's no excuse for sharp practice. It's true that cheap record players and audio systems often don't have a very accurate speed by hifi standards, though Dynatron stuff wasn't particularly low end. People coming to records for the first time may be very intolerant of pitch errors and variations, as the digital sources they're used to will be absolutely pitch perfect. Back in the day people just put up with it. That's not to say there isn't a fault present in this case of course. The deck probably needs a stripdown and relube.

14th Jul 2018, 12:23 pm	#5
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Help with Dynatron Calvacade music centre I haven’t a problem with the £100, including travel time it could have been 2 hours. It’s the time of day for a none urgent call that I find difficult to accept. I wouldn’t be opening the door at that time unless I knew the person. __________________ Frank

14th Jul 2018, 12:49 pm	#6
paullamey Retired Dormant Member Join Date: Jul 2018 Location: London, UK. Posts: 4	Re: Help with Dynatron Calvacade music centre Thanks for the advice. I think the person that came round did strip it and oil / lube the parts. I just have a feeling the belt might not be the right one - or that it's that that is causing the problem. Would someone be able to point me in the right direction for where to get some belts I could try? I've had a look online but can't find the right one where they're in stock. And £15 seems an awful lot for essentially on O ring! Or if anyone knows anyone in the London area that is good for repairs that won't charge me £100 and turn up near midnight! Thanks again for all your help. Appreciate it.

14th Jul 2018, 2:07 pm	#7
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Help with Dynatron Calvacade music centre Can you examine the belt which has been fitted? It should be tight enough not to slip, but not so tight so as to be significantly stretched. Turntable drive belts are usually quite long flat belts, though I don't know this deck. Belt design isn't usually very critical if the diameter is correct, particularly in this category of equipment. You can buy an assortment of belts for next to nothing, e.g. https://www.ebay.co.uk/itm/30pcs-Sma...gAAOSwUH5aXGud but there may not be a large enough belt and they will probably be square section rather than flat. Although you are unhappy with your repairman, he has at least dismantled and examined the unit, which is more than people commenting here have (including me). Did he have any comments to make about the problems, other than "they're all like that"?

14th Jul 2018, 2:20 pm	#8
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Help with Dynatron Calvacade music centre According to this they are a triangular belt. https://www.musonic.co.uk/101-origin...t-p-17879.html __________________ Frank

14th Jul 2018, 2:33 pm	#9
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Help with Dynatron Calvacade music centre It looks to me as if a flat belt of the right diameter would be absolutely fine as a replacement. Even a square belt from the cheap Chinese selection would probably be OK if it's the right size in other respects. Other sources suggest the belt is round or square section, so it probably doesn't matter much. From the photo, it looks as if this deck has a low voltage DC motor with electronic speed control. The speed fault may be being caused by this rather than any belt problem. Other sources say it has a synchronous motor though, so the Musonic illustration may be misleading.

14th Jul 2018, 2:37 pm	#10
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Help with Dynatron Calvacade music centre Could well be a low voltage motor, I cannot find any information about it though. __________________ Frank

14th Jul 2018, 3:07 pm	#11
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Help with Dynatron Calvacade music centre Found this page, not a lot of info but seems to be a synchronous motor. https://www.vinylengine.com/library/goldring/g101.shtml __________________ Frank

15th Jul 2018, 2:08 pm	#13
jamesperrett Octode Join Date: May 2007 Location: Liss, Hampshire, UK. Posts: 1,873	Re: Help with Dynatron Calvacade music centre I had one of these for a while and remember changing the belt on it. The belts are fairly thin - certainly thinner than I was expecting. As I remember it, the torque from the turntable is fairly low so even something like too much tracking force could slow it down. The one I had was fitted with a Shure M75-6 cartridge which I seem to remember was set to 3g of tracking force.

15th Jul 2018, 2:15 pm	#14
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Help with Dynatron Calvacade music centre Check the speed using a strobe disc with and without the stylus being in contact with the record? __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

15th Jul 2018, 2:26 pm	#15
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Help with Dynatron Calvacade music centre I think the platter edge actually has strobe markings. A traditional fluorescent light will provide a 50Hz strobe, though a compact fluorescent won't.

16th Jul 2018, 8:04 am	#16
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,761	Re: Help with Dynatron Calvacade music centre You can download strobe discs (for 50 Hz & 60Hz) free of charge from the vinylengine site here: https://www.vinylengine.com/strobe-discs.shtml Not sure if you have to be a member to download, (I'm a member), but like this forum, it's a simple process to join. That enables you to download (and upload) manuals FOC. Hope that might help a bit. __________________ David. BVWS Member. G-QRP Club member 1339.

16th Jul 2018, 9:40 am	#17
vidjoman Dekatron Join Date: Jun 2013 Location: East Sussex, UK. Posts: 3,326	Re: Help with Dynatron Calvacade music centre The belt used was triangular in shape and the groove in which it runs will have a 60 degree angle cut in it, not the 90 degrees needed for a square belt. A square belt will not work as it will be pinched in the groove of the motor drive and the turntable.

16th Jul 2018, 12:59 pm	#18
Beobloke Heptode Join Date: Oct 2007 Location: Southampton, Hampshire, UK. Posts: 821	Re: Help with Dynatron Calvacade music centre As vidjoman says, this is one deck where "any old belt that looks about right" will NOT work. The pulley groove is very deep and a round, square or flat belt will ride too far out and make the deck run fast.

16th Jul 2018, 3:16 pm	#19
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,947	Re: Help with Dynatron Calvacade music centre Maybe that's the symptom that the OP is complaining about?

16th Jul 2018, 3:22 pm	#20
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,846	Re: Help with Dynatron Calvacade music centre Just to clarify some of the above, this deck has a synchronous motor, triangular cross-section belt, very light aluminium platter with plasticy hub around which the belt runs, and has no strobe marking or means of adjusting the speed. The belt has to be just right or else it won't work satisfactorily. I was always disappointed with the performance of mine and ended up fitting a skip-found Dual 505 in its place.