CB77 & Gray 206 - UK Vintage Radio Repair and Restoration Discussion Forum

Robashard · 2nd Jul 2021, 7:03 pm

I have a pair of Gates CB77’s and two Gray 206’s to put on them.
I’m in the U.K. and I gather that these were originally ex BBC.
The motors are Moortronics and have 2uF motor capacitors on them.
I’m running off a step down transformer from 240v to 110v, and I got a transformer with them, so I know that’s how they were used.
The Moortronics motors seem to run very hot. If left on for over an hour, I’m aware that both the deckplate and the platter are becoming warm, and you can’t really touch the motor.
The motors both turn freely and I have added a bit of light machine oil to both top and bottom oiling tubes.
Some people have said these do run hot, but this seems a bit much to me.
I have replaced the 2uF motor capacitor but it doesn’t seem to make it run any cooler.

peter_sol · 3rd Jul 2021, 8:11 am

Strangely enough, the motors have 220v stamped on the label.

3rd Jul 2021, 8:38 am

And “Volt 115”, ho hum…

peter_sol · 3rd Jul 2021, 8:58 am

Ok. Yes. Perhaps the 220v refers to the capacitor minimum rating.

Analogue man · 3rd Jul 2021, 10:17 am

These decks were designed to have a fast start which was achieved by applying 220v for about 2 seconds before returning to 110v on the motor, the timing of the 2 second burst was by a relay.

I had a 16 inch version of this deck from the Radio London ship some years back and as I recall it too ran quite hot so it might just be the norm.

crackle · 3rd Jul 2021, 3:31 pm

Well I am sorry to say this they dont look like the sort of machine to play your valued records on.
Mike

Ted Kendall · 3rd Jul 2021, 3:37 pm

This combination was used in the first Radio 1 studios, with a Shure SC35, and worked pretty well, despite appearances. Most of the first tranche of Radio 1 DJs were ex-pirates and this gear was preferred wear on the ships because the stylus stayed in the groove. Mistracking does more damage to records than high tracking force, anyway.

Mr Moose · 3rd Jul 2021, 6:40 pm

Hello,
On the motor rating plate it says "RISE 25 C" so you would expect a temperature rise of 25 degrees C when running.
Yours, Richard

Robashard · 4th Jul 2021, 12:43 am

Don’t be fooled by the look of the arm, Crackle. It’s nowhere near as hefty as you might think as it’s made of magnesium, and it’s a very clever unipivot design with an ingenious ball-in-cup silicone damped setup. I’ve had experience of some Russco’s with the same arm and was very impressed with the audio.
No such relay exists to switch 240v briefly to make it start quickly on the CB77 or 500. It’s just brute force, ignorance, and an idler wheel as fat as a tape machine pinch wheel.

Robashard · 4th Jul 2021, 12:44 am

More on the quality of the Gates CB77. Rumble and wow and flutter-wise, it’s thought to equal a Garrard 301.

Robashard · 4th Jul 2021, 12:45 am

I believe the voltage you’re seeing on the motor refers to the motor capacitor rating.

2nd Jul 2021, 7:03 pm	#1
Robashard Triode Join Date: May 2021 Location: Dartford, Kent, UK. Posts: 11	CB77 & Gray 206 I have a pair of Gates CB77’s and two Gray 206’s to put on them. I’m in the U.K. and I gather that these were originally ex BBC. The motors are Moortronics and have 2uF motor capacitors on them. I’m running off a step down transformer from 240v to 110v, and I got a transformer with them, so I know that’s how they were used. The Moortronics motors seem to run very hot. If left on for over an hour, I’m aware that both the deckplate and the platter are becoming warm, and you can’t really touch the motor. The motors both turn freely and I have added a bit of light machine oil to both top and bottom oiling tubes. Some people have said these do run hot, but this seems a bit much to me. I have replaced the 2uF motor capacitor but it doesn’t seem to make it run any cooler. Attached Thumbnails

3rd Jul 2021, 8:11 am	#2
peter_sol Octode Join Date: Aug 2003 Location: Welwyn Garden City, Herts. UK. Posts: 1,906	Re: CB77 & Gray 206 Strangely enough, the motors have 220v stamped on the label.

3rd Jul 2021, 8:38 am	#3
Guest Guest Posts: n/a	Re: CB77 & Gray 206 And “Volt 115”, ho hum…

3rd Jul 2021, 8:58 am	#4
peter_sol Octode Join Date: Aug 2003 Location: Welwyn Garden City, Herts. UK. Posts: 1,906	Re: CB77 & Gray 206 Ok. Yes. Perhaps the 220v refers to the capacitor minimum rating.

3rd Jul 2021, 10:17 am	#5
Analogue man Hexode Join Date: Dec 2020 Location: Raunds, Northamptonshire, UK. Posts: 359	Re: CB77 & Gray 206 These decks were designed to have a fast start which was achieved by applying 220v for about 2 seconds before returning to 110v on the motor, the timing of the 2 second burst was by a relay. I had a 16 inch version of this deck from the Radio London ship some years back and as I recall it too ran quite hot so it might just be the norm.

3rd Jul 2021, 3:31 pm	#6
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	Re: CB77 & Gray 206 Well I am sorry to say this they dont look like the sort of machine to play your valued records on. Mike

3rd Jul 2021, 3:37 pm	#7
Ted Kendall Dekatron Join Date: Jul 2008 Location: Kington, Herefordshire, UK. Posts: 3,675	Re: CB77 & Gray 206 This combination was used in the first Radio 1 studios, with a Shure SC35, and worked pretty well, despite appearances. Most of the first tranche of Radio 1 DJs were ex-pirates and this gear was preferred wear on the ships because the stylus stayed in the groove. Mistracking does more damage to records than high tracking force, anyway.

3rd Jul 2021, 6:40 pm	#8
Mr Moose Octode Join Date: Jul 2008 Location: Gloucestershire, UK. Posts: 1,043	Re: CB77 & Gray 206 Hello, On the motor rating plate it says "RISE 25 C" so you would expect a temperature rise of 25 degrees C when running. Yours, Richard

4th Jul 2021, 12:43 am	#9
Robashard Triode Join Date: May 2021 Location: Dartford, Kent, UK. Posts: 11	Re: CB77 & Gray 206 Don’t be fooled by the look of the arm, Crackle. It’s nowhere near as hefty as you might think as it’s made of magnesium, and it’s a very clever unipivot design with an ingenious ball-in-cup silicone damped setup. I’ve had experience of some Russco’s with the same arm and was very impressed with the audio. No such relay exists to switch 240v briefly to make it start quickly on the CB77 or 500. It’s just brute force, ignorance, and an idler wheel as fat as a tape machine pinch wheel.

4th Jul 2021, 12:44 am	#10
Robashard Triode Join Date: May 2021 Location: Dartford, Kent, UK. Posts: 11	Re: CB77 & Gray 206 More on the quality of the Gates CB77. Rumble and wow and flutter-wise, it’s thought to equal a Garrard 301.

4th Jul 2021, 12:45 am	#11
Robashard Triode Join Date: May 2021 Location: Dartford, Kent, UK. Posts: 11	Re: CB77 & Gray 206 I believe the voltage you’re seeing on the motor refers to the motor capacitor rating.