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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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Old 4th Sep 2018, 3:41 pm   #21
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

OK I`m getting so close I can almost smell the success ..haha ... Transport is now working , the relay on the control board was blocked from working , however , one last thing to correct is the new fault where in STOP , the motors are spinning in opposite directions . Tape tension is working , if I lift the arms up , the motors slow / stop .
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Old 4th Sep 2018, 3:49 pm   #22
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

Its an grounding issue / short to ground somewhere because when playing a tape there is a god awful hum and the hum changes when pressing play / stop etc ... ohhhh ..how frustrating is the stuff ..haha ..I`ve been at this one for about 6 months , i gutted it , rewired it , spent hours and hours on it , waited 8 weeks for parts for it , so to say I`m getting a little excited is an understatement ..haha
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Old 4th Sep 2018, 4:35 pm   #23
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

This might be a power supply issue , voltages are low across the board . Although i assume they will be low given the motors are spinning , but I`m getting 28 where there should be 36 , 10 where there should be 12 , etc . I think its time to re-cap everything and then see what it does, it still has the orginal caps in it and they are all going to be leaking dc like a sieve aren`t they so I think I might get stuck into doing that and see how that turns out . Normally I would find the fault first , but I have a feeling there is a short cap in here somewhere . so .
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Old 4th Sep 2018, 4:53 pm   #24
ms660
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Default Re: Philips N4520 tape counter sensor.

What's the voltage output at the rectifier/reservoir?

Lawrence.
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Old 4th Sep 2018, 5:07 pm   #25
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

FIXED ..... Changed out 5 caps on the transport board . sorted . I need to test further I havent tested playback as yet . .... .brb
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Old 4th Sep 2018, 5:15 pm   #26
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

OK I still have hum of all hums on the audio , but transport is now kinda working , I have no rew/ff it performs the action but the reels don`t turn (as if its not man enough to spin ) and thats something that this machine just isnt , its got the craziest rewind I`ve ever seen ..lol . So I`m going to keep going with the re-cap because clearly some of them are knackered. Its going to take me most of the night because there are a lot in here but it`ll be worth it in the end . ..... I`ll carry this one once I`ve done . Thanks again for helping me out , its just wonderful to have such moral support to be honest . I spend my days on my own , locked in a world of soltude so its nice to have "friends" to turn to when you get low (stuck). Thanks folks .
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Old 4th Sep 2018, 5:41 pm   #27
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

I just checked the power supply and someone in their infinite wisdom has instead of putting 150uF caps in , put 15 uF caps in ...hahah ....thats not going to do it much good eh ..hahah .

Last edited by NorfolkDaveUK; 4th Sep 2018 at 5:53 pm.
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Old 4th Sep 2018, 8:27 pm   #28
NorfolkDaveUK
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Default Re: Philips N4520 tape counter sensor.

ITS FULLY WORKING .....

changed those caps out for the right ones (almost) and while i was doing that noticed one of the main filter caps had a lead off (cause of the hum) and I now have a fully working N4520 ...thanks everyone for the guidance , I really appreciate it so much .
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