Grundig TK3200, Drive belt size? - UK Vintage Radio Repair and Restoration Discussion Forum

stubbyeddy · 10th Feb 2012, 11:14 am

Hello, I recently got a Grundig TK3200 portable reel to reel, looks a lot like a Uher in appearance anyhow I'm after the drive belt size and if anyone as any info on the power supply connections? It takes 6 D size batteries and apparently if you have the power supply you can charge up rechargeable batteries but there's not a lot of information in English about the unit so if anyone has one or knows anything about it please help! I have stripped the unit down, cleaned and lubricated it and it's working fine, only a little bit of wow and flutter due to the drive belt having a bit of memory I assume. It's a very high quality little unit with very impressive record playback! Any info would be appreciated.

stubbyeddy · 11th Feb 2012, 2:29 pm

I just wanted to follow up with some high quality photos of the machine in question.

http://s1078.photobucket.com/albums/...dy1/?start=all

ricard · 13th Feb 2012, 6:44 am

Thanks for sharing the pictures. Always nice to see some interior shots.

I'm assuming the big round disk with the Siemens sticker and some red apparently flex pcb on it is the motor, presumably of some brushless variety?

stubbyeddy · 13th Feb 2012, 10:33 am

Hi Ricard

your right about the motor, the motor speed is reduced for the different play speeds, all the drive belt does is fast forward/rewind and drive the take up reel.

stubbyeddy · 15th Feb 2012, 7:22 pm

I get the impression this machine is quite rare, I cant find a lot out about it at all, especially in english. I bought it off a chap who had it in his loft for 30 years, it came when they bought the house and the original owner used it to record bird song as a hobby.

Has anyone seen one or worked on one in the past at all? I have measured the old drive belt. the inside diameter is 96mm with a 3mm thickness its a round belt. I guess the belt diameter needs to be reduced a little dew to stretching ect. Does anyone have anything like that size they can sell me?

ricard · 15th Feb 2012, 8:38 pm

If it's a round cross section belt you can always use a large diameter o-ring obtainable from a vendor that sells hydraulic seals. O-rings are made of slightly harder rubber than belts, so they are not really ideal, but on the other hand they are readily available.

stubbyeddy · 17th Feb 2012, 6:57 pm

Just to update I have fitted a new drive belt and after some tweaking, mostly adjusting the tension on the take up spool which looks to have been adjusted as the original belt was starting to age, as I just put the tension back to factory setting. Its working perfectly, Im just after a knob and some idea of how to get a power supply so I don't have to keep feeding it 6 D size.

I have attached a photo of the type of knob im looking for and one of the power connector.

the knob is overall 21mm long, and at the widest point 16mm (number ring) the center post is 7mm long with an inside diameter (D shape) 4mm. Im guessing Grundig may have used this style in other devices. Once again any help on this would be greatly appreciated

stubbyeddy · 21st Feb 2012, 12:36 pm

Update!! after sorting everything as described above I now have a massive wow problem, I have adjusted everything on the transport, reel tension ect, I have even stripped down the brushless motor and lubricated and still have a wow problem, I suspect the problem is to do with the power supply to the motor, maybe a bad component or something, I don't have the tools here to really go into testing components and alike so I was wondering if I could post this off to someone to have a look at it for me? there is no play in the motor or any of the bearings that could be causing this and the fact it seams to have gotten worse im pretty sure its a motor power problem. If anyone would be so kind as to have a look at it for me please do get in touch.

10th Feb 2012, 11:14 am	#1
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Grundig TK3200, Drive belt size? Hello, I recently got a Grundig TK3200 portable reel to reel, looks a lot like a Uher in appearance anyhow I'm after the drive belt size and if anyone as any info on the power supply connections? It takes 6 D size batteries and apparently if you have the power supply you can charge up rechargeable batteries but there's not a lot of information in English about the unit so if anyone has one or knows anything about it please help! I have stripped the unit down, cleaned and lubricated it and it's working fine, only a little bit of wow and flutter due to the drive belt having a bit of memory I assume. It's a very high quality little unit with very impressive record playback! Any info would be appreciated.

11th Feb 2012, 2:29 pm	#2
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Re: Grundig TK3200 I just wanted to follow up with some high quality photos of the machine in question. http://s1078.photobucket.com/albums/...dy1/?start=all

13th Feb 2012, 6:44 am	#3
ricard Octode Join Date: Mar 2006 Location: Lund, Sweden Posts: 1,632	Re: Grundig TK3200 Thanks for sharing the pictures. Always nice to see some interior shots. I'm assuming the big round disk with the Siemens sticker and some red apparently flex pcb on it is the motor, presumably of some brushless variety?

13th Feb 2012, 10:33 am	#4
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Re: Grundig TK3200, Drive belt size? Hi Ricard your right about the motor, the motor speed is reduced for the different play speeds, all the drive belt does is fast forward/rewind and drive the take up reel.

15th Feb 2012, 7:22 pm	#5
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Re: Grundig TK3200, Drive belt size? I get the impression this machine is quite rare, I cant find a lot out about it at all, especially in english. I bought it off a chap who had it in his loft for 30 years, it came when they bought the house and the original owner used it to record bird song as a hobby. Has anyone seen one or worked on one in the past at all? I have measured the old drive belt. the inside diameter is 96mm with a 3mm thickness its a round belt. I guess the belt diameter needs to be reduced a little dew to stretching ect. Does anyone have anything like that size they can sell me?

15th Feb 2012, 8:38 pm	#6
ricard Octode Join Date: Mar 2006 Location: Lund, Sweden Posts: 1,632	Re: Grundig TK3200, Drive belt size? If it's a round cross section belt you can always use a large diameter o-ring obtainable from a vendor that sells hydraulic seals. O-rings are made of slightly harder rubber than belts, so they are not really ideal, but on the other hand they are readily available.

17th Feb 2012, 6:57 pm	#7
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Re: Grundig TK3200, Drive belt size? Just to update I have fitted a new drive belt and after some tweaking, mostly adjusting the tension on the take up spool which looks to have been adjusted as the original belt was starting to age, as I just put the tension back to factory setting. Its working perfectly, Im just after a knob and some idea of how to get a power supply so I don't have to keep feeding it 6 D size. I have attached a photo of the type of knob im looking for and one of the power connector. the knob is overall 21mm long, and at the widest point 16mm (number ring) the center post is 7mm long with an inside diameter (D shape) 4mm. Im guessing Grundig may have used this style in other devices. Once again any help on this would be greatly appreciated Attached Thumbnails

21st Feb 2012, 12:36 pm	#8
stubbyeddy Pentode Join Date: May 2005 Location: Newtown, Mid Wales, UK. Posts: 186	Re: Grundig TK3200, Drive belt size? Update!! after sorting everything as described above I now have a massive wow problem, I have adjusted everything on the transport, reel tension ect, I have even stripped down the brushless motor and lubricated and still have a wow problem, I suspect the problem is to do with the power supply to the motor, maybe a bad component or something, I don't have the tools here to really go into testing components and alike so I was wondering if I could post this off to someone to have a look at it for me? there is no play in the motor or any of the bearings that could be causing this and the fact it seams to have gotten worse im pretty sure its a motor power problem. If anyone would be so kind as to have a look at it for me please do get in touch.