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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
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22nd Nov 2017, 12:04 am | #21 |
Hexode
Join Date: Mar 2012
Location: East Yorkshire, UK.
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Re: Pye Black Box Restoration
If you do decide on a rewind and need any help with it you could contact Forum member Ed Dinning. He re-wound my BB output transformer and did an excellent job. Quite close to you too.
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Howard |
22nd Nov 2017, 8:09 pm | #22 |
Octode
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Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
A rewind looks to be the best option. I will get in contact with Ed Dinning.
The replacement capacitors have arrived today. |
23rd Nov 2017, 4:42 pm | #23 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,548
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Re: Pye Black Box Restoration
Don't switch it on with the duff transformer. It won't prove anything that you don't already know and it may damage the output valves as they'll be running without anode volts so may overheat the screen grid.
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There are lots of brilliant keyboard players and then there is Rick Wakeman..... |
23rd Nov 2017, 5:15 pm | #24 |
Banned
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Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
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Re: Pye Black Box Restoration
Glad you established what was wrong with it before you changed all those capacitors?
Sorry for you that the transformer is duff but its better to find out sooner rather than after you have gone round and round looking for a fault you thought you have introduced whilst changing bits that is not there. |
25th Nov 2017, 2:43 pm | #25 |
Octode
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
I'll be making suitable arrangements with Mr Dinning soon for the O/P transformer to be rewound.
My to-do list at the moment:
The acos cartridge is likely duff and any NOS alternative will probably be the same. What is the output of the acos cartridge? I'm wondering if it can replaced with a conventional ceramic cartridge with a 1/2'' mount. Building a small preamp would be necessary if the original cartridge is of a high output type or if the new cart has a low output. Do the motor wires terminate in push fit connectors? I don't want to pull too hard in case I break anything. The cabinet does have some small pieces of veneer missing and is scratched in places. I know very little about cabinet refinishing. |
25th Nov 2017, 3:12 pm | #26 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
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Re: Pye Black Box Restoration
Out of interest, which section(s) of the transformer is (are) faulty?
Lawrence. |
25th Nov 2017, 5:35 pm | #27 |
Dekatron
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Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Pye Black Box Restoration
I do not recommend you attempt to re-use the 1955 Acos cartridge, it's for Mono records only, is heavy and may not even be working. You can still get a suitable medium output cartridge for your Black Box that will be stereo-compatible, a BSR X5M. But hurry as stocks of these are now dwindling fast. You may need to re-balance the tone arm to about 4.5/5 grams. As for the UA6 autochanger you can use gromments from Maplins to re-mount the motor. Stack them up so they are the same height as the originals. You may also need to have the rubber idler wheel (it drives the inner rim of the turntable) skimmed as these do not retract when not in use on this early model. Use IPA for cleaning and sewing machine oil for lubing. Avoid WD40! You may not need to replace all the paper caps, but there are some key ones in the tone and coupling circuts that will have to be changed. New values have changd slightly but will suffice e.g. an old 0.05uf will now be a 0.047uf.
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Edward. |
26th Nov 2017, 3:15 pm | #28 |
Octode
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Re: Pye Black Box Restoration
I'm not going to bother with the original cartridge. I'd like to experiment with ceramic cartridges that are still produced today. The output quoted online of these carts tends to be around 150mV-350mV. I think such output will be suitable to replace an old medium output cart. I don't want to rely on expensive NOS parts whose supplies are running out and could be defective.
This is the third and oldest idler wheel turntable I've dealt with. The idler wheel is in excellent condition, it is supple and grips well. The TT has been degreased and will be oiled once it has dried. The platter mat is in good condition. I'll buy some grommets tomorrow. The diameter required will be 10mm. I've replaced all of the paper capacitors with 630V replacements at the appropriate modern values. I've also bought replacement electrolytic capacitors but I'll see if the originals work without hum. I'm not too sure which sections of the transformer are faulty, but I do know that most sections read open and two give a reasonable reading in the hundreds of ohms. Last edited by OldTechFan96; 26th Nov 2017 at 3:16 pm. Reason: Extra |
1st Dec 2017, 1:41 pm | #29 |
Octode
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
The O/P transformer was sent to Ed on Wednesday.
I've replaced the original mains cable with 3m of new cable. The turntable and motor have been re-oiled and go through the motions as they should. The c clip is missing. I've ordered a ceramic cartridge which should arrive next week. Its output voltage is: Output voltage (at 1k Hz, 3.54 cm/sec): 150 mV ~ 300 mV. Its tracking range is:Tracking force: 5.0g (4 ~ 6g). The stylus comes with a sapphire tip. At the end of the tonearm there are a red, blue and ground wire. What are the red and blue wires for? I'll have to work out which wire goes where on the cartridge. |
1st Dec 2017, 3:14 pm | #30 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
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Re: Pye Black Box Restoration
The red and blue wires are for connection to your new cartridge. You should solder the original old Acos cartridge connectors to them and then push these on to the new cartridge pins. DO NOT solder the wires to the cartridge, you will ruin it. What type/make of cartridge did you buy - is it stereo (4 pins) or mono stereo compatible (2 pins)? At 150mV the output from this will be lower than your old Acos mono cartridge, so it may not play quite so loud. If it does produce as much as 300mV, then it should play at the original volume.
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Edward. |
2nd Dec 2017, 11:08 am | #31 |
Octode
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Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
Here is a link to the cartridge I bought. It is designed for stereo and has 4 pins.
Unfortunately the push-fit connectors are missing at the end of the two signal wires. I might have something suitable knocking around. |
2nd Dec 2017, 11:48 am | #32 |
Dekatron
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Location: Southwold, Suffolk, UK.
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Re: Pye Black Box Restoration
Ah, now we see it. To play back in Mono to suit your Black Box you will need to bridge the LH and RH channels together, otherwise you will only hear one channel from a stereo pressing. Obviously you can't use this for 78s. You will also need to adjust the tracking weight on the BSR UA8 tone arm. I think you can still buy the pin connectors from Musonic.
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Edward. |
3rd Dec 2017, 8:04 am | #33 |
Hexode
Join Date: Mar 2012
Location: East Yorkshire, UK.
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Re: Pye Black Box Restoration
These are the tags Edward referred to. I have used these myself.
http://www.musonic.co.uk/index.php?m...ex&cPath=24_33
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Howard |
3rd Dec 2017, 12:37 pm | #34 |
Octode
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Re: Pye Black Box Restoration
Thanks for the suggestion Howard. That it exactly what I need to finish off the turntable.
The model name of the cartridge I bought is STY 146. It may be a clone of a Sanyo or Sharp product. I have not tested the TT motor yet. I think that I'll wait until the amplifier is all back together first. |
3rd Dec 2017, 2:18 pm | #35 |
Dekatron
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Location: Heckmondwike, West Yorkshire, UK.
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Re: Pye Black Box Restoration
Be careful soldering these. It's easy to flood the wrong end with solder and you don't get a spare!
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5th Dec 2017, 12:17 pm | #36 |
Octode
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
I ordered some tags yesterday and should be here soon. I should have all the bits and pieces I need to get the BBH up and running, including the rewound O/P transformer from Ed, by the end of the week.
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5th Dec 2017, 12:30 pm | #37 |
Rest in Peace
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Re: Pye Black Box Restoration
That Cartridge is very similar to the currently available Chinese ceramic ones, though its output may be a bit higher. It, or one like it, was indeed fitted to various Sharp, Sanyo, and other record players, etc. in the 80's & 90's.
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7th Dec 2017, 5:33 pm | #38 |
Octode
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
The O/P transformer arrived at 4:00 and will be installed soon. I would like to thank Ed Dinning for a rapid rewind. The turnaround was just over a week!
The only thing that I'm waiting for now is the cartridge tags. |
7th Dec 2017, 9:20 pm | #39 |
Octode
Join Date: Jul 2017
Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
Good news, everyone! The BBH amplifier is working. I've had it on for 15 minutes while feeding an audio tone from my signal generator. There is no mains hum so I think the smoothing capacitors are good.
I will test the amp more later. |
12th Dec 2017, 3:01 pm | #40 |
Octode
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Location: Newcastle Upon Tyne, Tyne & Wear, UK.
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Re: Pye Black Box Restoration
Since the snooker is finished I've had the time to get on with the Pye BB.
I've installed the new cartridge in place and made sure that it is connected correctly. The records do play, but I have some problems and questions. The BSR UA8 has not been adjusted in any way. What adjustments do I need to make? The ones I know are tracking force, set down position and tone arm hight. The changer mechanism works. The record size lever works on 7'' singles but it is not consistent with 12" LPs. The tone arm moves into position then falls away from the record. I think that the output of the new cartridge is lower than I expected. When the volume is turned right the way up the BBH is not as loud as it thought it would be. When I tested the BBH with my signal injector the amp could pump out a hell of a noise. I will look into a suitable preamp. I was testing the BBH outside of its cabinet. The point of the stylus does not sit straight in the record groves. It looks to be on an angle. Could this be cured by adjusting the tonearm or does the stylus need to be bent slightly? I'll post photographs later. Thanks |