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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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21st May 2022, 9:48 pm | #21 |
Heptode
Join Date: Jan 2008
Location: Oslo, Norway.
Posts: 632
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Re: At my wits end with ICC5 Picture Fault
Looks to me as an EW-fault. I had a fault like this i a Philips set. The culprit was a small resistor. (It measured ok, but failed when stressed.)
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21st May 2022, 11:54 pm | #22 |
Pentode
Join Date: Mar 2016
Location: Champaign, Illinois, USA.
Posts: 227
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Re: At my wits end with ICC5 Picture Fault
What's an "EW" fault?
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22nd May 2022, 8:39 am | #23 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,550
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Re: At my wits end with ICC5 Picture Fault
'EW' = East West. Sorry....us olduns from the trade tend to use abbreviations which are not always obvious to the uninitiated! In other words, the suggestion is that it could be a fault in the East-West correction circuit.
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22nd May 2022, 3:17 pm | #24 |
Dekatron
Join Date: Sep 2006
Location: Kilmarnock, Ayrshire, UK.
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Re: At my wits end with ICC5 Picture Fault
Hi.
I've also had that fault, not on an ICC5 fortunately but on something else. Definitely EW issue and from memory an obscure one but I can't recall what or the chassis.
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22nd May 2022, 10:53 pm | #25 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
Posts: 492
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Re: At my wits end with ICC5 Picture Fault
So far all ive determined is there is a new issue that has now developed, i changed a few capacitors today and once done tried starting the set, set came on but instead of the usual deflection 'noise' a kind of running water noise was coming from the flyback and just a blank raster on the screen, i put the original parts back in and set came back as it was before, changed one cap again CL52 and set returned to the blank raster state, figured the replacment i used was a dud so put the original back in and was surprized to see the same blank raster issue...
left the set running for a minute while i thought of what could have happened and then i moved the board slightly and the screen came back so there is now an intermittent connection somewhere that I am going to have to hunt down before i try fix the EW Issue what i dont understand is how it wasn't present before... I've also had a thought that as per a suggestion from another member on here that i should use an IC Socket for the EW IC given how often they fail which I had done when I first got the set working again, im thinking can the IC Socket be causing the EW issues as I know they can cause problems
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22nd May 2022, 11:57 pm | #26 |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,562
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Re: At my wits end with ICC5 Picture Fault
Having to deal with intermittent faults is bad enough on a chassis that uses old style through-hole components but is far worse on chassis that uses surface mount components. The trouble with frequent handling of the chassis is that new faults can be introduced.
The way I'd approach this chassis is: 1. Thoroughly inspect the PCB for dry joints and damaged MELF parts. Also look out for electros that may have leaked. 2. Use an oscilloscope to check waveforms in the EW modulator circuit or at least use an analogue 20kOhm/Volt meter to check for variations when the fault is present. The list of faults exhibited by the ICC5 is considerable and when you're trying to run a reputable repair business and having unreliable sets with this chassis damaging customer relations it's easy to see why the ICC5 chassis was not popular in the trade. It's a shame because the sets are stylish and perform well (when working). The previous TX100 was far easier to service as was the earlier and I think better TX10. Regards, Symon |
23rd May 2022, 12:33 am | #27 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
Posts: 492
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Re: At my wits end with ICC5 Picture Fault
I've taken a break from the set after working on it for a few hours, its now got its picture but its intermittent, when the fault I originally posted the videos for begins to creep in its getting more erratic and the raster is now disappearing when it begins and the picture will only come back if I tap or move the set.
Will be diving back in to it in about an hour or so and first thing im going to tackle is the board for dry/cracked joints in the area i was working in earlier today as thats when and where this new fault seems to have begun from. I dont have a scope or analogue meter unfortunately so my testing is rather limited and I kind of have to rely on a swap it out and hope it works approach with the EW Issue. I will look at replacing some of the MELF components that look a bit suspect also. Cant see any evidence that any electrolytics have leaked but some could have dried up or gone high ESR I suppose
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23rd May 2022, 3:26 am | #28 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
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Re: At my wits end with ICC5 Picture Fault
intermittent Picture issue fixed...bad joint
now back to the original issue, I've uploaded another video showing a test card which may highlight the issue better, its almost like 'breathing' when there is a regulation issue but more erratic and it does 'snap' back into place so something in the set is realising and doing whatever it needs to do to compensate for the issue but its not enough as it recurs again seconds later and even when it does 'snap' back into place the E/W is still not correct even if the picture is stable https://youtube.com/shorts/xrrqox2eENc?feature=share hopefully this video may help narrow down which part/s may need to be tested/changed
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23rd May 2022, 8:46 am | #29 |
Hexode
Join Date: Jan 2013
Location: Kelvedon, Essex, UK.
Posts: 272
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Re: At my wits end with ICC5 Picture Fault
Have a look at this website
https://www.radios-tv.co.uk/vintage-...-stock-faults/ My experience is with 50's and 60's tv, but that latest video tells me that you have a power supply fault. John. |
23rd May 2022, 9:14 am | #30 |
Nonode
Join Date: Mar 2010
Location: Dukinfield, Cheshire, UK.
Posts: 2,034
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Re: At my wits end with ICC5 Picture Fault
As almost everything else has been suggested, dare I tentatively suggest a dagging problem? Intermittent/poor connections to the dag can cause all manner of symptoms from expanding/jumping pic to vertical rows of noise and general 'zaps'.
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23rd May 2022, 8:50 pm | #31 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
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Re: At my wits end with ICC5 Picture Fault
Still no further with this, as a test to rule out the LOPTx I swapped it with the one from my other ICC5 and its still behaving the same way so LOPTx is ruled out.
Does anyone have anymore suggestions as to where to look, ive gone over and over the board and there is no visible cracks or lifted pads. I used my 10x zoom on my camera to get as close as possible to MELF Components and I cannot see any visible cracks/lifted pads or dry joints
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24th May 2022, 11:51 am | #32 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
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Re: At my wits end with ICC5 Picture Fault
I'd just blanket resolder the entire timebase and horizontal section, been there done that on ICC5 chassis. Given the sets history there could also still be a hairline fracture in a pcb trace. Other more conventional causes for strange intermittent e/w issues could be a faulty trim potmeter or a wonky connection to the aquadag as was suggested above.
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25th May 2022, 2:46 pm | #33 |
Dekatron
Join Date: Aug 2006
Location: Madrid, Spain / Wirral, UK
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Re: At my wits end with ICC5 Picture Fault
from an old faults list , may be similar.
ICC6 WARM LINE TWITCH: TV71(BC858B/BC857C SM) ICC5 PIC FLUTTER CP37(4700UF). ICC5 PIC RIPPLE. TR107 L120.
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26th May 2022, 1:28 am | #34 | |
Pentode
Join Date: Mar 2016
Location: Champaign, Illinois, USA.
Posts: 227
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Re: At my wits end with ICC5 Picture Fault
Quote:
is very wide indeed at my latitude. |
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26th May 2022, 1:33 am | #35 | ||
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
Posts: 492
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Re: At my wits end with ICC5 Picture Fault
Quote:
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26th May 2022, 3:01 am | #36 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
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Re: At my wits end with ICC5 Picture Fault
Pincushion distortion is only one part of the (dynamic) E/W correction. Trapezoid, width, sometimes even other corrections as far as they pertain to the left to right aspect of the picture are also achieved through the E/W correction circuit. Some 90 degree designs that don't require an E/W correction circuit for pincushion distortion, still use the same circuit for setting the width.
Thomson real flat tubes even use (dynamic) N/S correction, mostly for gull wing distortion (as did delta tubes a long time ago). |
14th Jun 2022, 9:39 pm | #37 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
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Re: At my wits end with ICC5 Picture Fault
Quick update on this....
After changing an obscene amount of parts the set is still mostly behaving the same, by accident last night i accidently tapped off the heatsink the HOT is mounted on and the picture started 'trembling' for lack of a better word. Should have tried that ages ago because now i know ive either got a bad connection or broken trace ive missed. I'll have to really focus and spend a proper amount of time on it and investigate around the HOT area for cracks/bad joints
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15th Jun 2022, 11:47 am | #38 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
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Re: At my wits end with ICC5 Picture Fault
Do check the anchoring and earthing of the line output transistor's heatsink. A very similar fault ussed to happen on a Sony TV of the same era when a perfect looking earthing connection went high resitance intermittently. Similarly a slight tarnishing of the line driver transformer's connections can affect the waveform.
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17th Jun 2022, 11:24 am | #39 |
Hexode
Join Date: Aug 2018
Location: Dublin, Republic of Ireland.
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Re: At my wits end with ICC5 Picture Fault
I have the picture stable now in that its not 'trembling or stretching' like it was in the videos i posted but the E/W Trapezium and Pincushion is still not correct, i can get 80% correct but after it runs for a bit it gets worse
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17th Jun 2022, 11:30 am | #40 |
Dekatron
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Re: At my wits end with ICC5 Picture Fault
That Luke sounds like you are in the right area.
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