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Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc. |
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16th May 2022, 8:00 pm | #1 |
Tetrode
Join Date: Sep 2016
Location: Tring, Hertfordshire, UK.
Posts: 87
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EMI BTR2 Tape Recorder.
I have been asked to help with a BTR2 machine as a last attempt to save it.
It has been stored for many years and I would like to know a little about these machines before I attempt to switch on. Has anyone any knowledge on their operation? Even better does anyone have any service notes. I have noticed what appears to be lubrication points filled with felt which are totally dry. What sort of oil is suitable or would 3-1 be ok? Any help, however small , would be great. Many thanks Mike |
16th May 2022, 9:29 pm | #2 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
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Re: EMI BTR2 Tape Recorder.
I have a BTR2 service manual. It is quite a thick book with quite a lot of pull out pages so scanning is quite tedious although I do have scans of most of the electronics.
I will check tomorrow on the recommended lubricants. I would disconnect all of the amplifier modules before powering up and get the deck working first, then go through the amplifiers one by one. There are several versions, with or without PPM meter unit and power amplifier. There are also sometimes different amplifiers used if the machine was originally supplied to EMI studios. BBC units would have had special remote operation circuits. |
16th May 2022, 9:38 pm | #3 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: EMI BTR2 Tape Recorder.
Very interesting machine.
The video clip at the end shows 2 of the oil wells. https://www.youtube.com/watch?v=oH56HpSwsQk David |
17th May 2022, 5:57 am | #4 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
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Re: EMI BTR2 Tape Recorder.
The manual states that the oil reservoirs should take Wakefield Loom oil (Wakefield Oilit) - this is contained in the lubrication kit QD.441/A......
Any general purpose light machine oil is probably O.K. though 3-1 would not be my first choice as it tends to dry up over a period of time. Do not overdo it and check for leaks before going too far, you don't want oil running all over the place. |
17th May 2022, 6:49 am | #5 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
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Re: EMI BTR2 Tape Recorder.
I should probably add that since the machine is between 60 and 70 years old oil is the least of your problems.
Before you power up the deck you should check all the likely components, caps and metal rectifiers mainly, and bring the power up slowly watching for smoke. |
17th May 2022, 8:24 am | #6 |
Tetrode
Join Date: Sep 2016
Location: Tring, Hertfordshire, UK.
Posts: 87
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Re: EMI BTR2 Tape Recorder.
I will follow Barry's advice on starting with the deck.
Without applying power I can rotate the spool motors. The capstan motor refuses to rotate but there may be a brake mechanism? There are also two large 500uf 50v caps that are bulging. All other caps will also be changed so I think this is going to be slow progress. The unit has two front panel meters and six amplifier/power supply units. No one knows the original owner. |
17th May 2022, 9:19 am | #7 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
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Re: EMI BTR2 Tape Recorder.
There is a brake band on the capstan flywheel, which is supposed to be fluid filled, I don`t know how well sealed they are or how fluid the fluid would be after all this time.
If there are six amplifier units it has the meter amplifier and power amplifier. The power amplifier is rated at 8 watts, which seems a bit stingy for a pair of KT66s. Is it a 7.5 /15 ips machine or 15 / 30 ips? capstan diameter will tell you. A 15 / 30 machine will have a capstan diameter of just over 3/8 inches. |
17th May 2022, 10:45 am | #8 |
Hexode
Join Date: Jan 2006
Location: Greater Manchester, UK.
Posts: 373
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Re: EMI BTR2 Tape Recorder.
I have the full BTR-2 manual in electronic format 63Mb....not sure if it is too big to send as an PM attachment?
PM me and let's see where we get to...? |
17th May 2022, 4:34 pm | #9 |
Tetrode
Join Date: Sep 2016
Location: Tring, Hertfordshire, UK.
Posts: 87
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Re: EMI BTR2 Tape Recorder.
Hi Stevie,
Would it be possible to try to send the manual. Would this be to my email address? Although I read this forum each day I am not totally sure how it works. Mike |
17th May 2022, 4:38 pm | #10 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: EMI BTR2 Tape Recorder.
Some email systems will cap the maximum file attachment size (for a single file or accumulated total of several files) that can be emailed to 20Mb or less.
David |
17th May 2022, 4:40 pm | #11 | |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: EMI BTR2 Tape Recorder.
Quote:
David |
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17th May 2022, 5:29 pm | #12 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
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Re: EMI BTR2 Tape Recorder.
63Mb sounds like PDFs. It may be possible to put these into a ZIP folder to reduce the size if that has not already been done.
I doubt it is sensible to do it via PM, direct to a real email address would be better. I have done this type of thing in the past by sending multiple emails. |
17th May 2022, 5:44 pm | #13 |
Octode
Join Date: Jul 2004
Location: Dundee, UK.
Posts: 1,797
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Re: EMI BTR2 Tape Recorder.
Have you considered a bulk transfer application such as Dropbox or Wetransfer, both of which can be used without charge?
PMM |
17th May 2022, 7:57 pm | #14 |
Nonode
Join Date: May 2016
Location: Cornwall, UK.
Posts: 2,315
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Re: EMI BTR2 Tape Recorder.
If you use Thunderbird it will walk you through uploading a file to a bulk transfer host if it detects you attempting to send a large attachment. Alternatively, as pmmunro says, go to wetransfer.com, upload on the left and send the link in your e-mail.
PDFs can usually be optimised (File>Save as optimised PDF) and if OCR Text Recognition is used this helps as it knows words rather than rasters. Also very handy in general for manuals as it enables searching for keywords. I use the attached as an aide memoire for powering up old things. |
17th May 2022, 11:16 pm | #15 |
Hexode
Join Date: Jan 2006
Location: Greater Manchester, UK.
Posts: 373
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Re: EMI BTR2 Tape Recorder.
One has Onedrive and dropbox....it is a pdf already......
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23rd May 2022, 11:35 pm | #16 |
Hexode
Join Date: Jan 2006
Location: Greater Manchester, UK.
Posts: 373
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Re: EMI BTR2 Tape Recorder.
I can post the schematics pretty sure they will fit and I cut the large pdf down to smaller ones which will fit on here and then post them.
What is the file size limit here? Sorry I did not get it done this weekend something cropped out so had to deal with that today I have been playing catch up....it will get done in the next few days or so.....OK |
24th May 2022, 8:52 am | #17 |
Tetrode
Join Date: Sep 2016
Location: Tring, Hertfordshire, UK.
Posts: 87
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Re: EMI BTR2 Tape Recorder.
Thanks for your efforts Steve.
So far I have inspected each module and made a list of the capacitors that need changing. Now each unit has been cleaned their condition is reasonably good. All cables appear to be in the right connectors although some had been left disconnected. The replay amp does have a sub-chassis that is floating around. It appears that it should sit on 6 rubber mounts. This and it's power supply will be the first units re-commissioned. So without applying any mains it is still looking impressive. Mike |
24th May 2022, 9:36 am | #18 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
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Re: EMI BTR2 Tape Recorder.
When attaching files to a Forum post it states that max file size for PDF's is 4.00MB, I assume this is per each file of the 5 max files that can be attached.
David |
24th May 2022, 7:59 pm | #19 | |
Hexode
Join Date: Jan 2006
Location: Greater Manchester, UK.
Posts: 373
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Re: EMI BTR2 Tape Recorder.
Quote:
As for the Manual I can break that down as much as i can into sections as in the manual - I may have to break them down a bit more to get them to fit. I can see it is going to be several replies to get them all together in one place. It does not matter if it is all split up as long as you print it out or merge them all back together.....but do not worry busy for the next few days but will get round to it. |
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29th May 2022, 11:13 pm | #20 |
Hexode
Join Date: Jan 2006
Location: Greater Manchester, UK.
Posts: 373
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Re: EMI BTR2 Tape Recorder.
Ok here is something to get you going....I have other schematics as well too brain dead to do too much today...will work on it and try to get the full manual broken down and posted asap.
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