UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Closed Thread
 
Thread Tools
Old 28th May 2017, 8:44 pm   #1
collisr
Pentode
 
collisr's Avatar
 
Join Date: Oct 2016
Location: Ware, Herts, UK
Posts: 169
Question Philips V2000 - 2nd Generation Video Head compatibility

Hi all,

I was asked a question today which I couldn't answer - maybe someone on here knows.

I have a Philips VR2324 (Video 2000) machine which either has failing heads or perhaps the brush-contacts to the head drum.

Anyway, someone I know has a VR2340 and a 21VR20/22VR20 and we wondered whether the heads would be transplant-able into my VR2324. Any ideas?

I've been told the upper head drum was a pig to re-align after removal - is this true? Any tips?

Thanks

Rob
collisr is offline  
Old 28th May 2017, 11:01 pm   #2
greg_simons
Octode
 
greg_simons's Avatar
 
Join Date: Jul 2004
Location: Evesham, Worcestershire, UK.
Posts: 1,415
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Without the special plastic drum carrier and the two plastic shims replacement of the head drum on these machines is difficult as they accomplish two vital tasks, namely setting the head drum position correctly relative to the motor shaft position plus setting the air gap between upper and lower drum correctly, as to whether the parts are physically compatible i'm not sure if they are exactly the same.
greg.
greg_simons is offline  
Old 29th May 2017, 1:33 pm   #3
collisr
Pentode
 
collisr's Avatar
 
Join Date: Oct 2016
Location: Ware, Herts, UK
Posts: 169
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Thanks Greg. I think I'll hold on for a VR2324 junker, then see if I can replace the entire video and cassette loading component over. (The power board was recently serviced for me - new caps etc, but the heads appeared to be dead).

Regarding the upper drum replacement - is there any advice for setting the air gap correctly - or is it "keep securing it in different positions until the picture is clear of noise" ?

Rob.
collisr is offline  
Old 29th May 2017, 9:49 pm   #4
greg_simons
Octode
 
greg_simons's Avatar
 
Join Date: Jul 2004
Location: Evesham, Worcestershire, UK.
Posts: 1,415
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Hi rob,
the plastic shims set the air gap, it was really simple you dropped the drum onto the shaft with the shims in position and then tightened the lock screw after which the shims could be pulled out and the drum retainer removed, they were really plentiful because every new drum came equiped with a set of shims and retainer, but that was thirty odd years ago, it's possible someone on this forum may still have such items they could lend you.
regret i'm unsure about the shim thickness, they were very thin, just a few thou.
hope that info helps.
greg.
greg_simons is offline  
Old 30th May 2017, 9:32 pm   #5
samjmann
Heptode
 
samjmann's Avatar
 
Join Date: Feb 2014
Location: Nottingham, UK.
Posts: 645
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Hi,
Only ever did a head swap the once on these, and the drum came from Philips without the mylar spacer shims! At the time Philips were making VHS drums with a similar mounting arrangement, apparently you can use these shims for the V2000(as told by Philips TLO). So if anyone has an NOS head drum for a later Philips VHS (original turbo deck) you can use these for upper/lower drum spacing. Unless you really have to, I wouldn't split the upper/lower drum. SJM.
samjmann is offline  
Old 5th Jun 2017, 8:57 am   #6
collisr
Pentode
 
collisr's Avatar
 
Join Date: Oct 2016
Location: Ware, Herts, UK
Posts: 169
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Thanks Guys. All good advice. As I don't have access to the spacer shims, looks like a simple upper-head-drum swap out isn't on the cards for me.

Will look out for the VHS NOS head adverts incase they include some.
collisr is offline  
Old 5th Jun 2017, 1:29 pm   #7
Maarten
Dekatron
 
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,184
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

It should be possible to use a sheet of paper as a shim, but I'm not sure which weight it should be. The thickness of the shim is probably documented somewhere.
Maarten is offline  
Old 5th Jun 2017, 3:13 pm   #8
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,884
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

I imagine two pieces of card would do but the thickness is critical.
Don't you also need the red plastic cover that aligns the upper and lower drum? I know you did with the VHS versions. I remember buying a top of the range turbo deck for very little money when they were almost new from an ex-rental outlet. They thought there was a serious problem when in fact the heads were misaligned.
Glyn
Welsh Anorak is offline  
Old 6th Jun 2017, 3:21 am   #9
Maarten
Dekatron
 
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,184
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

The cover isn't needed, but later VHS models used a pin for the position alignment. Earlier VHS models didn't. I'm not sure about VCC.

The thickness might not be _that_ critical as I know someone (a former car mechanic who tinkered a bit with videorecorders when they were still in demand second hand) who used to swap VHS drums by just eyeballing the gap.
Maarten is offline  
Old 23rd Jun 2017, 8:53 am   #10
simpsons
Octode
 
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,483
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Replacing the upper cylinder which contains the heads is not difficult at all.

The spacer shim(s) can be easily made using an old 35mm film negative now called shim.

The most important point is to make sure the heads are kept out of the way of the shim.

Because it is easy to damage the heads, make sure that they dont hit the cassette carriage when aligning the drum to the shaft. Place the shim where the upper cylinder meets the fixed drum and rotate the heads out of the way. Lower the cylinder onto the shim, tighten the fixing nut whilst, using a pair of long nose pliers, stopping the threaded screw from turning. When tightened, lift the cylinder slightly and remove the shim. Job done.
simpsons is offline  
Old 24th Jun 2017, 12:26 pm   #11
collisr
Pentode
 
collisr's Avatar
 
Join Date: Oct 2016
Location: Ware, Herts, UK
Posts: 169
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Thanks for the advice simpsons.

Tried this today and didn't quite get the result I was hoping for. Using the film negatives as spacers/shims, I now get a constantly rolling picture, as if the machine cannot track. I also experimented with different, larger gaps between upper and lower head drum and as the gap increased the picture stabilised (stopped rolling) but an increasing bottom part of the screen was "grey noise" as if only part of the video track was being scanned. This made sense to me as the heads were effectively scanning higher and higher on the tape as I made the head gap bigger, missing more and more of the bottom of the tape.

But... why when I make the gap the correct height (using the film negatives as spacers) would I lose all tracking and have the picture continuously roll?

Any ideas?

Rob
collisr is offline  
Old 24th Jun 2017, 6:04 pm   #12
TonyDuell
Dekatron
 
Join Date: Jun 2015
Location: Biggin Hill, London, UK.
Posts: 5,190
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Shouldn't the track following servo (the bit that drives those piezo actuators that carry the heads) adjust the heads to follow the track and thus the height of the upper drum is not too critical (provided it's not so far out that the servo can't cope)?

Is it possible there's a problem with this servo or the power supply (it uses a couple of high-ish voltage rails)?
TonyDuell is online now  
Old 25th Jun 2017, 10:53 pm   #13
simpsons
Octode
 
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,483
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Hi Rob

I suggest that you first reset the head height using just one thickness of the 35mm negative which is the same thickness as the original philips shims.

It is possible that the head is past its sell by date but first listen to make sure the sound is at the right speed and also see that the head is spinning without hunting.

The heads rotate at some 1500 rpm so that with tape passing at a constant speed, each rotation scans or plays back a frame of the 50 Hz video.

The video servo will compensate for some errors as described in the service manual, but only within certain limits.

If possible try another recording or make one to see what happens.

There are certain pre-set adjustments to the servo but unless they have been got at, I would leave them alone. Changing a head shouldn't require further work.

Chris
.
simpsons is offline  
Old 26th Jun 2017, 3:45 pm   #14
collisr
Pentode
 
collisr's Avatar
 
Join Date: Oct 2016
Location: Ware, Herts, UK
Posts: 169
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

Thanks Chris/Tony.

I am quite puzzled by this -and appears half of the service manual I have is missing which isn't helping -esp the DTF stuff.

Agree it could be the heads on their way out, but looking at them carefully, they don't appear chipped or broken. Audio is always perfect BTW and I can't hear any obvious movement/hunting on the heads during play.

Setting the head gap back to the width of one-35mm negative , I get a rolling picture on all tapes, as if the DTF tracking isn't working at all (the tapes play fine on my VR2022). To Tony's point - if the head gap is made larger, surely the DTF should activate to try and follow the tape - not just show a grey-noise bar happily at the bottom of the screen!

It is possible the machine was "played with" before I got it. Have either of you got a copy of a complete VR2324 manual that includes the DTF circuitry and adjusters? I have no idea how to test the actuator servos (or where they are - although I assume inside the drum?) - but am suspecting they are the issue.

R.
collisr is offline  
Old 27th Jun 2017, 12:13 am   #15
simpsons
Octode
 
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,483
Default Re: Philips V2000 - 2nd Generation Video Head compatibility

OK

Google the Philips VR2220, visit page 2 and www.doctsf.Modèle : VR 2220. Année : 1983 schematic and circuit description can be downloaded albeit in Dutch.

This should give you enough to see how Philips designed the VR2324 you have.

I will pm you a copy of the Television Magazine description of the V2000 DTF.

As the tape works in your other machine see if you can record something on the VR2324 and see what the VR2020 does with it.

Chris
simpsons is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 5:41 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.