My Commodore 1084 Monitor Just Died! 😫

[C128User]

My much-beloved 1084 monitor, that has so faithfully served me from the 1980's, just died. I am lost; I cannot use my beloved Commodore-128 without it!

I offer $200.00 (negotiable) plus shipping costs to the first person able, and who undertakes, to repair it.

Please please please please please please please please please please!!!

Please reply to me directly at C128User@FoxValley.Net

Thank you!

 

[Hugo Holden]

I could fix this VDU for you, but it won't help much because I'm in Australia. Shipping it here and back would cost about $200 but its a very risky proposition.

What you need to do, if you cannot be helped to fix it yourself on the forum, is to find someone as close as possible to you, who can do it, so ideally you could drop it off and collect it, to avoid shipping damage. Hopefully there is someone close to you who can do it.

Often though, when something "dies" it can be as simple as a fuse or fusible resistor. Do you have a meter and have the ability to read circuit diagrams and use a meter and some knowledge of electricity & electronics ?

 

[HanJammer]

My much-beloved 1084 monitor, that has so faithfully served me from the 1980's, just died. I am lost; I cannot use my beloved Commodore-128 without it!

I offer $200.00 (negotiable) plus shipping costs to the first person able, and who undertakes, to repair it.

Please please please please please please please please please please!!!

Please reply to me directly at C128User@FoxValley.Net

Thank you!

1084s are known to fail due to flyback transformer failure (however you would have to specify which model exactly you have - is it 1084s-p1?). Finding an exact flyback you need may be a challenge though.

 

[C128User]

1084s are known to fail due to flyback transformer failure (however you would have to specify which model exactly you have - is it 1084s-p1?). Finding an exact flyback you need may be a challenge though.

So far as I can tell it is a plain 1084. If it helps, I could post a picture of the rear ports & controls.

 

[C128User]

1084s are known to fail due to flyback transformer failure (however you would have to specify which model exactly you have - is it 1084s-p1?). Finding an exact flyback you need may be a challenge though.

BTW, what is a "flyback transformer"???

 

[daver2]

It is the transformer that generates all of the high voltages required by the cathode ray tube (CRT).

In my experience, as Hugo has stated, there could just be a fuse (or fusible resistor) that has gone. Fusible resistors just age and can die. This is the case with monitors used by the Commodore PET.

When I used to repair equipment as a teenager and student, the most common failures were simple ones.

Another thought for you, is there an 'old fashioned' TV repair shop where you live?

Can you see if any of the manuals here match the physical monitor you have: http://www.zimmers.net/anonftp/pub/cbm/schematics/monitors/index.html?

If so, we can take it from there. Do you have a multimeter at home?

Dave

 

[Hugo Holden]

It is interesting that when a TV or a VDU fails, the immediate assumption is its the "Flyback" Like the atom who said to the other, "I have lost an electron" and the other atom says "are you sure ?" yes, I'm positive.

How this flyback transformer blaming game came about in popular culture, I'm not entirely sure, folklore and internet videos never helped the case.

While it is true that flyback transformers can and do fail at times, more often than not it is another issue such as failure in the power supply distribution. And when that is not the case, the failure in the H output stage transistor (HOT) occurs far more frequently as a failure of the H output transformer itself. I know this from 50 years of repairing TV's and VDU's.

One thing that made the demonizing of flyback transformers happen, possibly was that as time went by there was a lot less money for service shops in repairing TV's and VDU's, they became cheaper disposable items, and it was easy to say to the customer, after the screen on their TV or VDU went black; "well its the Flyback you see and its not economical to replace it, and even if we wanted to we cannot source the part".

One of the very first transistor TV's that I acquired as a teenager in 1975, was stone dead with no picture and no EHT. The set was a decade old then. What had actually happened was that the H output transistor failed. It was not appreciated by many TV service people back then (who had mainly worked with tube TV's), that this transistor requires special properties, especially for a Germanium pnp part. It must have a very low storage time and very high collector voltage rating. There was no internet to search transistors, the transistor equivalents books were not helpful and a limited supply of any suitable part in NZ at that time. So somebody had fitted a typical TO-3 audio style Germanium part, so it just sat there heating up. They concluded that the Flyback Transformer was defective and deemed the set un-repairable. At that time there was only one or two transistor (aside from the Japanese original part) that would worked, the RCA 2N3731 and an AU prefix part available in the UK. It took me a while to get a 2N3731, and nothing was wrong with the flyback transformer, it still works to this very day, nearly 50 years later, the story about this Sanyo TV is here:

www.worldphaco.com/uploads/Sanyo_s_amazing_8-P2_Televsion_set_from_1962.pdf

 

[C128User]

1. "Do you have... the ability to read circuit diagrams and... some knowledge of electricity & electronics?"

2. "Is there an 'old fashioned' TV repair shop where you live?"

3. "Do you have a multimeter at home?"

ANSWERS, IN ORDER: 1. No. 2. No. 3. No (WHAT is a "multimeter"??).

 

[daver2]

A multimeter is a piece of test equipment that enables you to read basic electronic parameters such as voltage, current and resistance. For example: https://boxed2me.co.uk/product/merc...4658?msclkid=84d6c07fea9a146a0f3fa733a4fb31fc.

Multimeters were given away with electronic magazines at one time and were sold at petrol stations for a couple of pounds / dollars.

They can be used to check whether fuses are blown or not, check the terminal voltage of batteries to see whether they are charged or flat, check that equipment is earthed etc.

They can be used around the house and car (for example) to see if the correct voltages are present where they should be. In a car scenario, multimeters can be used to check if the fuse is blown or not. If not, whether the accessory switch is working or not etc. to try and pinpoint the fault.

In our case, they can be used to check whether the internal fuse is blown or not (you can also do this visually if it is a glass fuse) and whether any of the fusible resistors have gone open circuit. Again (depending upon their construction) it may be possible to do this check visually. I suspect, from the age of your monitor, this may not be the case - and we might have to check the resistance of these items with a multimeter.

There are many people who have joined VCFED with zero knowledge of electronics and (in some cases) and with some help have managed to repair their computer/monitor themselves.

Dave

 

[cjs]

3. "Do you have a multimeter at home?"
ANSWERS, IN ORDER: 3. No (WHAT is a "multimeter"??).

If you don't know what it is, how do you know you don't have one? :-)

More seriously, a multimeter is one of these things:


It may look complex, but it's not that bad, really. You can ignore many of the functions on it; there are only a couple you need for basic troubleshooting.

That said, though even basic electronics itself is not so tough (I learned it in middle school), opening up a monitor for the first time is a pretty intimidating experience. None the less, I have even "arts" friends (degree in Theatre) who have become rather good at basic electronics troubleshooting with some support and after a little practice.

That said, it's perfectly understandable if you don't want to get sucked in to all that stuff, and just want a working monitor back. Do be very careful about packing it for shipping; from what I understand U.S. shipping services tend to abuse packages fairly severely.