Amplifone HV Printed board

[dezbaz]

Do you have the "magic part" MCI for new boards ?

I found this page regarding the MC1 Can (From here)

They miss-spelt amplifone so it is hard to find in a search

MC1 is labeled as "Magnetic Correction 1", hence you would be right, this
compensates for not having a yoke. But, if you read what I had to say about
replacing this - with 3 10mh chokes - this may be a possibility in a new
circuit.

Overall, the amplfione HV unit is a very simple design that could most
likely be adapted to any HV transformer.

Interesting

 

[Level42]

The SW doc set I bought from e-bay some years ago actually contained an updated schematic of the HV board showing the resistors (R20 & R21) and the extra added diodes (CR5 & CR6). The latest Amplifone FAQ mentions that the resistors were not in the schematics IIRC so I guess this is pretty rare ? Don't know.

I've attached it to this reply.....

 

[dezbaz]

The SW doc set I bought from e-bay some years ago actually contained an updated schematic of the HV board showing the resistors (R20 & R21) and the extra added diodes (CR5 & CR6). The latest Amplifone FAQ mentions that the resistors were not in the schematics IIRC so I guess this is pretty rare ? Don't know.

I've attached it to this reply.....

Thank you

so that means the mod will look like this (smaller) IE from a Beige Board

click


2 wire links are needed (see above)

Thanks for the help Level42 and others who replied

The shunts end up in the gap near the MC1 can

 

[Level42]

Yes that seems to look correct. I'd suggest to move the left power resistor a bit more to the left if possible. The more evenly the tranistors and resitors are spaced over the heat-sink, the better I guess....

I think the beige boards already have positions for the diodes right ?

 

[dezbaz]

Yes that seems to look correct. I'd suggest to move the left power resistor a bit more to the left if possible. The more evenly the tranistors and resitors are spaced over the heat-sink, the better I guess....

I think the beige boards already have positions for the diodes right ?

The diodes are just soldered on to the solder side. (3 diodes)

OOPS best to add them too

And it is easy enough to move the 1st resistor now so will do

Cheers

 

[dezbaz]

3 X Diodes added
2 x Medium size wire links needed
2 x Shunt resistors needed

Time to get these started I think

Thanks for the help

 

[TimothyC]

Time to get these started I think

Have you made any progress with this project dezbaz ? Like many others around here I have a 19" Amplifone with no HV board.

 

[Deadly]

Have you made any progress with this project dezbaz ? Like many others around here I have a 19" Amplifone with no HV board.

While every component is readily available the MCI can to my knowledge is not. There is a guess made as to what it really does or what it is.
So without that component this project is a mere PCB swap to get rid of burned up one

Might want to ping Daviea as I believe he is also working on a solution.

 

[dezbaz]

Have you made any progress with this project dezbaz ? Like many others around here I have a 19" Amplifone with no HV board.

I need to soon, but other projects, including my recent starwars c/pits, have put this off.

Do you realize, this is a BARE PCB manufacture? You will need to source the parts.

 

[dezbaz]

While every component is readily available the MCI can to my knowledge is not. There is a guess made as to what it really does or what it is.
So without that component this project is a mere PCB swap to get rid of burned up one

Might want to ping Daviea as I believe he is also working on a solution.

MC1 is explained earlier in this thread. I have already purchased the 3 x 10mH inductors to test it out on my cab.

I guess we just have to try.

Please note guys, I am in no hurry to do these, as I have a working amplifone board, but I will be doing it, in time.

If anyone is interested in a BARE PCB, then please jump on the list

I will edit page 1, post #1, every time someone asks to be included.

 

[dezbaz]

I am hoping to get these done soon

I have asked a reputable business owner, who actually designs and sources quality pinball and arcade parts and solutions.

I have directed Mike to this thread, so I am hoping he will chime in soon.

His name is Mike, from Homepin.

 

[Level42]

About the MCI: why hasn't anyone x-rayed one yet ? It's been done before with the sealed in IC's on various PCB's....

Would we expect to be able to see anything on an x-ray, I actually do think so....

I do have a friend who does x-raying in hospitals....mmm, I'll drop him a question....

 

[dezbaz]

About the MCI: why hasn't anyone x-rayed one yet ? It's been done before with the sealed in IC's on various PCB's....

Would we expect to be able to see anything on an x-ray, I actually do think so....

I do have a friend who does x-raying in hospitals....mmm, I'll drop him a question....

MCI is actually MC1
Magnetic Correction.

Apparently it's just a choke

 

[Level42]

MCI is actually MC1
Magnetic Correction.

Apparently it's just a choke

Apparently....that's the whole issue isn't it....

 

[Mike Doyle]

The SW doc set I bought from e-bay some years ago actually contained an updated schematic of the HV board showing the resistors (R20 & R21) and the extra added diodes (CR5 & CR6). The latest Amplifone FAQ mentions that the resistors were not in the schematics IIRC so I guess this is pretty rare ? Don't know.

I've attached it to this reply.....

Quantum didn't have the diodes (typically a blue PCB), the revision used in Star Wars did (usually green or beige). It's easy enough to add them to the earlier revision though.

 

[dezbaz]

Quantum didn't have the diodes (typically a blue PCB), the revision used in Star Wars did (usually green or beige). It's easy enough to add them to the earlier revision though.

I designed the proposed PCB with spots for all of the mods incl the diodes. If not needed, people can leave them off

 

[Level42]

The entire Amplifone PCB set in my SW cockpit was original (all the same Serial nr.) and I have blue boards. The HV did have the diodes (on the solder side) factory modded in as well as the resistors (on the parts side).

 

[dezbaz]

3 X Diodes added
2 x Medium size wire links needed
2 x Shunt resistors needed

Time to get these started I think

Thanks for the help

This the proposal, as used previously in the thread

 

[Level42]

What's the third diode ?

 

[dezbaz]

Mine had a diode there