Garrard 3000: wire power mod, proprietary connectors, rotting cables

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scrapjack+
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Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by scrapjack+ » 19 May 2019 21:21

I Have a Garrard 3000, along with the receiver from a record cabinet. I want to setup the Garrard on it's own plinth instead of having them both in the same shell just in case the receiver is placed too high to use the table on top of it. The Garrard 3000 is powered by some weird proprietary or obsolete 4 "pin" cables. They look almost like the modern 4 pin computer power molex connectors. Modern molex cables have round pins and a tool that I was never successful with to remove and install pins in their connectors. Most of these connectors have wedge pins that I don't think I can get replacements for. Since I hate finding stereo "components" that only have proprietary connectors, I'd like to split the wiring so that the Garrard could also function as a normal record player if paired to a modern amp.

I suspect the Garrard 3000, takes line voltage, and think mine is a two pole motor. The motor has a socket with only two leads. I can always cut the cables short from the connectors, try to strip the gooey insulation, then braid new wire on to the bare leads to solder before using shrink tubing. Wow, when I break it down, sounds like a lot of work. Is there a better way to go about restoring proprietary, or despairingly obsolete connectors?

All the interior proprietary connectors I'll probably try to restore, but for wires that will become external, I think I need to come up with a new plan. The problem with restoring some of the original wiring is that it was meant to be internal wiring, not external wiring. I am not convinced having 4 loose wires with interior circuit type insulation carrying mains current strewn across the table is safe.


I think I need to find a new type of panel mount 4 pin 120VAC cable to connect the amp and the table. Does anyone have a suggestion for an exterior mains current 4 pin cable? Is there a connector commonly used for this purpose?

I thought about using 4 pin CB microphone type connectors, which lead me to the GX16 aviation plugs. They seem to have high enough voltage ratings. If I can get a female panel mount for the amp power output, and a male panel mount for the turntable power input, I think that would be a safe patch cable, provided I can find some 4 wire extension cord.
A connector something along these lines. https://www.ebay.com/itm/5-Pairs-GX16-4 ... 3a1e33bab5
Working Voltage: 250V
Working Current: 15A
Withstand Voltage: 1500V AC
Insulator Resistance: 2000 Ohm

or this one https://www.ebay.com/itm/Panel-Mount-Av ... Sw96FcknlX
Opreation Limit Voltage AC 250V.rms
Withstand Voltage AC 1200V
Insulation Resistence Max. 1000 ohm
Contact Resistance 20 Ohm

Many sellers volunteer no specs. Seems like the information given is all over the place with these. This gold plated one offers acceleration force rating, but not the voltage. https://www.ebay.com/itm/2-Pair-Reverse ... ctupt=true
Specification:
Contact resistance: <0.01Ω
Insulation resistance: >500MΩ
Connection: sodier
Weight:about 24g/1 set
Pin Number: 4
Plug Diameter: 16mm
Ambient temperature: -50 ~ +70 oC
Relative humidity: up to 98% at +40 oC
Atmospheric pressure: up to 4.4 kpa
Vibration: vibration frequency 10 ~ 100Hz, acceleration 100m/s2
Impact: Frequency of 60 to 80 beats / min, acceleration of 250m/s2
Centrifugal: acceleration 250m/s2

Does the insulation resistance matter if a connector is rated at 200 volts and will only receive 110VAC? For this purpose, isn't the only info I need the max voltage, max current, and the contact resistance?

I have seen multiple power surges burn, sometimes literally, electronics in homes. I've also encountered things that developed grounding issues, like PC towers and those old pot metal power tools. Don't ever trust a pot metal power tool. I've learned, just because something is supposed to be insulated, or was at some point insulated, doesn't mean it actually is, years later. Anyway, I know surge protectors are the answer to power surge related concerns, and all my stuff is plugged into them. That said, If I am altering the circuit in this Garrard, I want to improve it the best that I can. I intend to give it a EMI filtered C14 socket with a built in fuse holder, however I need to figure out which wires to connect this way. I also need to figure out what the correct fuse would be to use, for a Garrard 3000. I realize the fuse in this orientation will only work if the table is powered by the wall plug instead of the amp. I also realize that the table should never have a wall cord plugged in at the same time as the amp power cord. What I am trying to say, Is that I want to improve the circuit to better protect the turntable and myself. The safety ground protects me, and the fuses help protect the turntable.

I could have sworn I saw a thread here about someone else wiring a Garrard 3000 to be stand alone, but none of the search terms I tried found it.

On my Garrard 3000 the screw is on the tapered side of the 4 pin connector. With the screw on top, counting left to right, the pins are 1: black motor lead, 2: blue motor lead, 3: continuity with blue lead when switch is in the "on" position, 4: signal ground. There is no continuity between the signal ground and the record player chassis. If I wanted to power this table as a stand alone table wouldn't I just need to connect the hot wire from mains to pin 1, and the neutral wire to pin 3, then use the existing switch.

If I'm giving the receiver a safety ground, I'd like to ground the Garrard chassis to the receiver chassis. Would that present any problems as far as the signal ground?
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A70BBen
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Re: Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by A70BBen » 20 May 2019 00:14

Wow...

Two cautions: the Garrard plug/jack is an Amplok type. Power cords for the Amplok connector are sometimes sold by EBay vendors. The ones for BSR changers will interchange.

And some phonographs derived power for their amplifiers from a motor winding. I don't think yours is like that but some of the 1000/2000/3000 series were. For the most part they would have been vacuum tube (valve) sets.

scrapjack+
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Re: Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by scrapjack+ » 20 May 2019 04:03

A70BBen wrote:
20 May 2019 00:14
Wow...

Two cautions: the Garrard plug/jack is an Amplok type. Power cords for the Amplok connector are sometimes sold by EBay vendors. The ones for BSR changers will interchange.

And some phonographs derived power for their amplifiers from a motor winding. I don't think yours is like that but some of the 1000/2000/3000 series were. For the most part they would have been vacuum tube (valve) sets.
Thanks, that name did find me a plastic housing for the larger connectors, sadly the odd shaped internal pins weren't available. It seems with old tech, finding the right search terms is at least half the battle.

Both the radio unit and it's power chassis are solid state with printed circuit boards. I think some models with the same radio unit had vacuum tube power chassis instead of the one I got.

You make the motor sound like the speaker coil B+ filtering on tube radios. As I understand some cabinets used an extra lead off the turntable as an on/off switch for the preamp, based on the tone arm position I think. Are you suggesting instead some amps use the motor coil itself as a core part of the amps circuitry? The combined receiver has a separate power chassis from it's radio input switchboard circuits. I can't seem to find any info on either, other than similar models existed in the 60's.

I thought all I had to worry about on the receiver end was whether it was a live chassis, which may affect how things should be grounded. I have not yet looked into how to determine that. A service manual would have told me, if I could find one.

BrianMcAllister
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Re: Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by BrianMcAllister » 16 Jul 2019 21:39

If you still need that cord and connector, This will work, but does not include the grounding wire, which would have to be a separate wire attached to the metal baseplate.

http://www.thevoiceofmusic.com/catalog/ ... Base=CordA

scrapjack+
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Re: Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by scrapjack+ » 18 Jul 2019 19:35

BrianMcAllister wrote:
16 Jul 2019 21:39
If you still need that cord and connector, This will work, but does not include the grounding wire, which would have to be a separate wire attached to the metal baseplate.

http://www.thevoiceofmusic.com/catalog/ ... Base=CordA
Thank you. While I think I am going to go a different route with this build, I'll probably pick up one of those for testing other tables.

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Re: Garrard 3000: wire power mod, proprietary connectors, rotting cables

Post by DSJR » 24 Jul 2019 09:19

Lord that old 3000 has some glued-up grease on it - have fun - loads of threads here and on the UK vintage radio site regarding cleaning off, what to re-lube and what not to...

To use as a stand-alone deck, the two pole motor really prevents a durable MM cartridge being used in the 3000 arm (some 3g trackers are fine mechanically and the Stanton 500V3 is the closest modern equivalent to the sister brand Pickering that was often fitted). depending on the ceramic type no doubt fitted to the arm, you'll need a proper very high (input) impedance input which isn't served by a typical modern 'Aux' socket. I don't wish to confuse you or anyone else, but it's worth looking up the needs of a typical ceramic cartridge of yore.

These things do come up from time to time, and that's a four pole Garrard 'laboratory series' motor plus wiring loom and switch. Make sure it's from an 'autoslim series' model and the correct frequency for your locale.

Apologies for over-complicating things, but I do have a very soft spot for the 3000 deck and feel it is worth the hassle if you can find suitable parts. This arm came with half inch cartridge mounts, unlike most of the other more basic models and if you're that way inclined, great fun to do...

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