9th Jan 2017, 9:18 pm | #41 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
The only other possible cause is the next IC’s back in the signal path, please see Fig XV1-4 circuit diagram, Vertical Decoder, Unit 5.The V15-16 signal to IC 18/1 comes from IC10/2 and V16-17 signal comes from IC11/4 to IC18/2. Without having an oscilloscope to check the only thing I can suggest is to replace IC10 and IC11 7402 (Quad Two Input NOR gate), one at a time and note the results. If this does not prove to be the fault move back to IC7/1 (7400) and IC8/3 also (7400) then try IC6/I and IC6/3 (both of these gates are in the same package) (7402). If you have already bought some spare 7400 IC’s you could try replacing IC7 and IC8 first. I hope this information is of some help. Regards Stan.
__________________
Junk accumulates to fill the space available. |
10th Jan 2017, 7:59 am | #42 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hi Stan
Thank you, i will try this. The IC's are not very expensive. Regards SkySat |
13th Jan 2017, 12:35 pm | #43 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hi Stan
Unfortunately still no success... Following IC's have I replaced: Unit5 - IC10 & IC11 (7402) Unit5 - IC7 & IC8 (7400) More Ideas? Regards SkySat |
14th Jan 2017, 3:05 pm | #44 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
Whilst I have a think of what to do next could you check the positions of the PCB’s part numbers against the ‘U’ slot numbers. Also have a look at the edge connectors where the PCB’s plug in and check that none of the white plastic card keys are damaged by someone in the past forcing the wrong card into the wrong socket. I have had this happen before causing damage to the gold plated edge connectors and intermittent contact with the PCB and missing signals. (Note sometimes these white plastic card keys are not fitted) Please check the position of the cards against the back plane drawing on page 54. Also could you send a picture of both sides of the Unit 5 PCB so that I can check the revision numbers and layout of the card, just in case we are working off the wrong drawing? Regards Stan.
__________________
Junk accumulates to fill the space available. |
15th Jan 2017, 8:41 pm | #45 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hello Stan.
Yes, the PCB are all in the right Slot. There are no Damages on the Sockets. I cleaned also the Connector with Alcohol & Air pressure. I've attached the Photo from the PCB Unit5. Regards SkySat |
15th Jan 2017, 9:43 pm | #46 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
Thanks for the pictures I will check the drawings I have to make sure we are working off the correct revision of the drawing. Regards Stan.
__________________
Junk accumulates to fill the space available. |
20th Jan 2017, 10:24 pm | #47 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Ok. Thank you Stan.
|
21st Jan 2017, 1:39 pm | #48 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
One more Picture. You see the lower Castillation is also missing.
|
21st Jan 2017, 9:11 pm | #49 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
Thank you for the photo showing the missing castellation. From checking through all the different revisions of the PM5544 I am beginning to think that the fault is further back on Unit 4 Vertical Divider PCB. However this board has been modified and revised on a number of occasions. Would you take a picture of your Unit 4 PCB on both sides so that I can determine which revision is fitted to your unit and I will post the relevant service information, as the timing for the divide by 16, centre line and circle start stop all come via Unit 4? Regards Stan.
__________________
Junk accumulates to fill the space available. |
22nd Jan 2017, 9:09 am | #50 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hi Stan
Here are the Pictures from Unit 4. |
22nd Jan 2017, 8:15 pm | #51 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
Your Unit 4 is one of the more modern versions. I will scan the relevant parts of the manual for you and post it later. The later revisions of this board is much simpler than the older versions but the drawing does not show the signals that can be displayed with the test amplifier, so I will add a copy of the older version of the circuit drawings which show the signals at the edge connector terminals. The input and output terminals and signals are the same only the board logic is different. Regards Stan.
__________________
Junk accumulates to fill the space available. |
22nd Jan 2017, 9:08 pm | #52 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hi Stan
Many thanks in advance! ;-) Regards skysat |
23rd Jan 2017, 4:03 pm | #53 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
Please find attached PDF copies of the service information for Unit4 (Vertical Divider) and a copy of the circuit diagram for the early version of the PM5544 Unit 4 which has different logic to drive the core memory circle generator. However the inputs and output signals from the edge connectors are shown on the diagram and you will be able to check these signals by using the Test Amplifier and your monitor. I have also attached a copy of the early version of the PM5544 Unit 5 diagram which also has the signals expected at the edge connector terminals, shown on the diagram; again the signals at the edge connector terminals are the same, only the logic on the PCB is slightly different. Before we jump in and start changing any more IC’s, can you check the signals with the test amplifier and compare with the images as indicated on the respective pins of the edge connectors on the drawings. I am particularly interested in the signal on edge connector 63’ on Unit 5, as this is where the missing line V16 should come out of the decoder. This signal comes from IC1/1 (7400) and the other gates in this IC control the oscillator start stop signals. Regards Stan.
__________________
Junk accumulates to fill the space available. |
24th Jan 2017, 9:45 am | #54 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hello Stan.
Thank you for your explanation. I've compared the Signals with my Monitor. In the attachmend you find the piture from Unit 5 - connector 63’. Regards skysat |
24th Jan 2017, 9:53 am | #55 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
You see in the Second picture, the typical faulty Picture, that must be an Circle.
|
24th Jan 2017, 9:56 am | #56 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
More Pictures vom the Connector from Unit 4...
|
24th Jan 2017, 9:57 am | #57 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
One more from Unit 4.
|
24th Jan 2017, 12:40 pm | #58 |
Heptode
Join Date: Jun 2010
Location: Zurich, Switzerland
Posts: 538
|
Re: Philips PM5544 Faulty
Hallo,
I think they would need a Pin-Nr listing too for some easyer "deshifring"... Karl |
24th Jan 2017, 3:25 pm | #59 |
Hexode
Join Date: Jul 2008
Location: Gateshead, Tyne & Wear, UK.
Posts: 337
|
Re: Philips PM5544 Faulty
Hello Skysat2
I am puzzled by the image on terminal 63’ on Unit 5, as it should be a single horizontal line in the centre of your monitor. I have attached a PDF copy of the edge connector terminal key and marked the +5 and 15 volt supply rails. If you measure these voltages on pins 1’ and 2’ on the edge connectors, which should be at the rear of the instrument, this will give you the correct orientation of the edge connector terminals. Please check the other signals and state which image is from which terminal number on which unit. Regards Stan.
__________________
Junk accumulates to fill the space available. |
25th Jan 2017, 11:26 am | #60 |
Tetrode
Join Date: Dec 2016
Location: Bern, Switzerland.
Posts: 60
|
Re: Philips PM5544 Faulty
Hello Stan.
The Power Supply on the Connector on Unit 5 Terminal are ok! +5V on 1' and +15V on 2'. The Photo on Unit 5 Terminal 63' are really that, what i'm posted above. (I have now at Home 6pcs from SN7402, and 13pcs from SN7400 that i can replace on any Unit.) Regards SkySat |