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-   -   Philips N1500 - can it be tricked? (https://www.vintage-radio.net/forum/showthread.php?t=175355)

The_Archiver 16th Jan 2021 9:19 pm

Philips N1500 - can it be tricked?
 
2 Attachment(s)
Hello everybody, and all the best for 2021.
Have decided to have another go, after several years, at repairing a second-hand N1500. This one has a partially damaged threading pulley, but notwithstanding that, it did get to almost fully laced position when last used, after a thorough clean and new belts.
Whilst I do have NOS pulley and lacing cord set (still factory sealed!), am wondering if I can ‘trick’ the machine by using the bracket [blue arrow on second picture] attached to the drum, to assist to fully laced position after PLAY is pressed. Theoretically, could this work, and is there any shock risk from this bracket? Trying to replace the pulley looks extremely fiddly, made worse with poor eyesight for close-up work.
As well as the above, having had issues in the past with the mains filter capacitor on a Sanyo Betacord and ITT V2000, is there such an item on the N1500 also, should it be replaced first, and are there any other specific capacitors that should also be replaced? [I do not have an ESR meter.]
Many thanks.

Philip

The_Archiver 23rd Jan 2021 5:58 pm

Re: Philips N1500 - can it be tricked?
 
Mods, may as well close this thread as nobody is interested.

Cobaltblue 23rd Jan 2021 6:02 pm

Re: Philips N1500 - can it be tricked?
 
I will close it if you wish (or one of the other Mods) but it may be simply no one knows if this will work or not.

I would give it a couple of days see if anyone with intimate knowledge of this machine can come to your aid.

We can always close it later.

Cheers

Mike T

nigelr2000 23rd Jan 2021 10:58 pm

Re: Philips N1500 - can it be tricked?
 
My 1701 was easily fooled by removing the top cover on the cassette housing and pressing the tape sense (maybe another name for it but tha'ts what I call it) lever that sticks up on the bottom of the cassette housing. It would lace up and happily perform it's functions with no tape in.

mark pirate 24th Jan 2021 11:26 am

Re: Philips N1500 - can it be tricked?
 
There is a lot of info on these machines here: https://www.youtube.com/channel/UC7I...Wh5--Lmo623Qaw
I am sure I watched how the machine could be tricked on a recent video.

:beer:
Mark

Maarten 26th Jan 2021 12:39 am

Re: Philips N1500 - can it be tricked?
 
Assisting seems like a bad idea as these machines have a reputation for causing more damage when you use them with a failing threading mechanism.

The_Archiver 27th Jan 2021 2:17 am

Re: Philips N1500 - can it be tricked?
 
Mike, Nigel, Mark, and Maarten, thanks to you all.
An update is that I found amongst the box of spares that included the NOS lacing cord set (including pulley), another [used] pulley only. Have now installed that and manually tested the whole loading mechanism without power, by using a screwdriver in the flat groove in the top of the loading motor spindle, and, all rotates as it should.
New belts are already here to be fitted, so hopefully the machine should be ready to try with power within the next few days...
Oh to have a 1501 or 1502!

Philip

af024 27th Jan 2021 10:16 am

Re: Philips N1500 - can it be tricked?
 
Yes the N1501 and N1502 do seem to be more rare don't they.

As for the lacing up mech, well I never really understood why Philips went with this idea. It all seems a bit Heath Robinson. I remember chuckling to myself when the mod with more springs and fishing-type line was added to draw the main strings out of the way of the head drum in the event of main string breakage. Of course it's even more fun now that the years have taken their toll on the pulley and small gear, especially if it fails in a manner not to shut the lacing sequence down. You just end up with ruined springs and a stalled (and probably damaged) motor!

All part of the fun I suppose.

Actually, looking at the manual (lubrication section), it looks like they have shaded the wrong area for greasing. It shold (presumably) be the groove and not the face. Ow well.

Regards,

Andy

Welsh Anorak 27th Jan 2021 11:02 am

Re: Philips N1500 - can it be tricked?
 
At least Philips learned their lesson, or so we thought. Charlie deck anyone?

Maarten 27th Jan 2021 11:21 pm

Re: Philips N1500 - can it be tricked?
 
At least the Charly deck doesn't use lacing cord do they seem to have learned ;)

The_Archiver 11th Feb 2021 6:11 pm

Re: Philips N1500 - can it be tricked?
 
Finally, an update. Loading mechanism repaired, new drive belts fitted, plugged into mains, and initial test without a tape gave the result that the head drum revolves into place with the head spinning well, and the machine stays on (which I think is correct for that operation).
When tested with a tape, laced up well and correctly, but after a second or so, unlaced correctly and switched itself off. Green indicator light does not come on (bulb to be checked first), and will then consult the service manual, but if anyone has any suggestions I would be very interested to hear and try them.

Philip

The_Archiver 13th Feb 2021 4:00 pm

Re: Philips N1500 - can it be tricked?
 
2 Attachment(s)
OK, after further investigation it appears that switch SK12 may be having difficulty changing state at the supposed end of the lacing up operation (to be tested again with a cassette soon), but purely by coincidence when checking the mechanics in the bottom of the machine, switch SK11 remains in the same state in both STOP and START mode as the protruding part with the orange coloured sheath (shown in photos) is unable to make contact in either mode.
Am trying to find reference in the Service Manual as to what SK11 is for, so if anyone knows, or thinks the switch actuator is being blocked in some way from full travel, I would be very grateful.
The bulb for the green indicator is working, but this may only light up when a colour signal is being received.

Philip

The_Archiver 16th Feb 2021 8:48 pm

Re: Philips N1500 - can it be tricked?
 
2 Attachment(s)
All previously mentioned switches checked and working, alternative and shorter head drum drive belt fitted, and the bloomin’ machine works! Except, I am assuming (possibly not able to tell from attached screenshots, which show a rather youthful looking Patrick Moore) that there is issue with sync lock...?
Audio is also very patchy, and although adjusting the tracking and audio switches does help, the picture is still unwatchable.
Any ideas on how to proceed always welcome. Haven’t given up yet!

Philip

The_Archiver 20th Feb 2021 7:31 pm

Re: Philips N1500 - can it be tricked?
 
Another update. More suitable head drum drive belt has now been fitted, and the results are at:

https://www.youtube.com/watch?v=aq9rhU-h4Gs

Does this indicate servo issues in the playback section of the machine?

Philip

nigelr2000 20th Feb 2021 10:10 pm

Re: Philips N1500 - can it be tricked?
 
Looks like the capstan is slipping as the picture looks locked suggesting the head servo's working fine. Got for the easy stuff first check the pinch rollers engaging properly.

The_Archiver 20th Feb 2021 11:11 pm

Re: Philips N1500 - can it be tricked?
 
Nigel, thank you for that.
I have both a NOS pinch roller and idler wheel, so will first change the former and record another video for comparison if the outcome is improved or different. Fingers crossed.

Regards.

Philip

The_Archiver 21st Feb 2021 11:26 pm

Re: Philips N1500 - can it be tricked?
 
Looks like it’s the start of a long and laborious task of checking components on boards now, as pinch roller has been checked for engagement with the capstan, new idler fitted, all belts doing what they should, all mechanicals checked, but there is still the horizontal picture roll as per the YouTube link given in 20th February post [that upload will remain in case anyone has any further suggestions].

Thanks to all for thoughts and assistance, and will post here again if the machine does get sorted.

Philip

HurtyAC 22nd Feb 2021 10:29 am

Re: Philips N1500 - can it be tricked?
 
Hi All,
It looks like the capstan is not running fast enough. Most likely mechanical problems rather than electronic. Do you have a scope? If so you need to scope the capstan trapezoid and see which way the the sample pulse is running as it will not be locked looking at your pictures, I would say the capstan is running slow. Next disconnect a wire off the eddy current brake for the capstan and it will probably still be running slow? It should run fast at this point! Add a drop of thin oil to the upper and lower bearing of the capstan motor and see if this improve things. Some tapes are starting to "drag" on 1500's I find the Scotch tapes tend to do better than the Philips tapes.

af024 22nd Feb 2021 10:35 am

Re: Philips N1500 - can it be tricked?
 
Amazingly I had a similar problem and put it down to the capstan belt. It wasn't that the belt was sloppy, it seemed that it was too thin. On face value you might say so what, but I came to the conclusion that it was running too deep into the drive pulley, thereby running in a smaller diameter. If you temporarily and manually nudge the belt to the large diameter of the pulley (ie out of the pulley groove and onto the pulley shoulder), it might just lock (as mine did). Also, I've found that these machines were not brilliant at synching up material recorded by other machines. Have you tried to record something on your machine and playing that back?

The_Archiver 22nd Feb 2021 5:44 pm

Re: Philips N1500 - can it be tricked?
 
Quote:

Originally Posted by HurtyAC (Post 1344877)
Do you have a scope?

HurtyAC, thanks for your post. No scope at present, and that’s another question: any recommendations as to whether or not digital scopes are any good, or would it be better to try and obtain something more akin to what I remember from high school back in the 80’s/90’s?
Quote:

Originally Posted by HurtyAC (Post 1344877)
If so you need to scope the capstan trapezoid and see which way the the sample pulse is running

Apologies, but am not versed in electronics at all, could you explain what you mean by the “capstan trapezoid”?

Many thanks.

Philip


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