FS Parts: Run 2: Amplifone High Voltage PCB & Rare Parts - Repro

dezbaz

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Run 2: Amplifone High Voltage PCB & Rare Parts - Repro

Hi Guys

HV Reference Thread

Some people have asked for High voltage gear (same as sold approx 12 months ago) to be included.
Some have asked for info too

Hopefully this thread will answer your questions

Threads
Deflection for sale thread (Still current)
High Voltage for sale thread (Expired - old thread)
Amplifone Neck Boards for use with 8 Pin TVs


Assembly Guide for the Reproduction Deflection PCB (Mar 2013)

Assembly Guide for the Reproduction High Voltage PCB (Mar 2013)
 
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hey dezbaz,

What is needed to make a complete HV pcb for an amplifone if we have a complete deflection board?

Thanks
Grant

The PCB
Bare_PCB-01-sm.jpg


The Electronic Parts (DIY) See this list

An alternative neck connector
NeckConn-sm.jpg


OR- This 8 pin neck connector (But a few mods are needed)
See here
http://forums.arcade-museum.com/showpost.php?p=2421470&postcount=96

Some pics of the 8 pin neck board are in post #2 (Limit of 8 pics in post #1)

A Harness (DIY) Possibly to be done by Joeycuda: IE this is the deflection Harness thread, but it's discussed in there

A Mystery Can 1 Repro
MC1_Laquered-sm.jpg


A Transformer 1 Repro
Repro_T1-sm.jpg


3 Pieces of glued heatshrink to do the Focus block Mod HERE
HS_Glued-sm.jpg


An Amplifone Flyback (Bob Roberts, Twisted quarter, Arcade Shop etc)

A WG6100 Flyback (Bob Roberts, Twisted quarter, Arcade Shop etc) Used only for the Focus block. You need to do this mod
FocusBlockCrop-sm.jpg


When it's all assembled, this Setup has to be done (Overvolt limit AND voltage adjustment)

You will need a TV Tube: (Process discussed here) 25" TV in a SW thread
 
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  • NOTE: Known issues arriving from original HV Board
  • If using a WG6100 Focus block, R19 needs to be 100K
  • If using an original Amplifone Focus block R19 needs to be 68K
  • The 12 Pin header on the neck connector needs to be a good brand (Like those sold by twistywrist etc) Cheapie ones cause intermittent picture) I suggest soldering the wires straight on maybe
    NeckConn-sm.jpg

  • If using an Amplifone 19" Tube (Rauland M48AAW00X) the CRT Neck protrudes longer than a TV does. The orig Neck connector looks like this
    Neck_Connector_Amplifone_Resistors-sm.jpg
  • It has a hole in it. SO the longer neck fits through the hole.
  • However if using the new Neck Board on a Rauland M48AAW00X tube, there is no hole in the Repro PCB and it may need to be drilled out
    WG_K7000_Neck-Amp.jpg
  • Picture above is an example, not the Repro item!!
  • You need 2 x metal parts too and hardware (Takeman's thread) I bought all of Troy's stock, and had some of the Heatsinks made locally (Still unpainted) when Troy's painted ones ran out. I have very limited numbers of them, and less focus block brackets
  • HV Heatsink
  • Screws to suit etc
  • The T1 Transformer needs to be fitted last. It is very close to a resistor, so longer legs were fitted to the T1 so it can be "higher". This gives clearance to the resistor (almost) below it
  • On the screen print, no number "8" was printed, as the font I selected was a Windows font, rather than a Vector font.
  • The picture of the LED on the screen print looks more like an arrow

Additional Info

A compatible tube will likely contain a neck config like this
 
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I didn't realize you were using 6100 focus block assy's , do they seem to work ok ?

Yes

Great focus, better than the Amps (Some of my orig Amps run out of focus before a good pic was acheived)

I had to change resistor R19 to 100K on my revision board. I am not sure how that would work on other revisions. (Using the 68K, the board would never cutoff during over volt conditions)

The resistor was part of the HV cutoff circuit. You could do this on any rev PCB as long as you experimented with the HV cutoff to get it right.

EDIT . . . Following on from this thread it was realized;
NOTE: Later revision beige and green boards are different, and have a 1K resistor in R19. They are not the same schematic
 
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NOTE:
The neck connectors will be supplied with no Molex straight plug from now on

Wires to the neck board should be soldered directly to the neck PCB due to intermittent problems caused by poor connections

NeckConn-sm-NO_Molex.jpg
 
Troubleshooting a newly build HV Repro

After building a HV board from scratch (8 pin CR31 Neck), I had a new problem

Symptom: HV board, R13 (39 ohms) burns out instantly upon application of power

Cause: Incorrect Transistor in Q2
Item fitted: MPSU-57
Should be: MPSU-07

Replaced R13, replaced Q2, tested: OK
 
Want to use a WG6100 Focus block on an Amplifone Green board?

NOTE: Soon to do . .

I will be modifying 1 x bare HV PCB so it works like a GREEN HV Board

There are some differences in the HV cutoff between this repro PCB version (Similar to the cream board) and the green boards

The reason for building a scratch green board is to allow the HV cutoff to work correctly if an original green board needs a new focus block

It will tell us the value of resistors etc that would need changing

TBA . . . . it's on the to do list
 
Symptom: HV Will not cutoff at 25KV (Smitty420's board), however board generates HV as normal

Possible cause: Second hand WG6100 Focus block in place of a new one

This has not been confirmed, but next chance I get to simulate this I will. May need to change R19 to a different value again

Anyone else got this same symptom?
 
I read somewhere, I believe it was amplifone frequently asked questions that the Chinese flybacks were not capable of the 25kv needed for cutoff therefore could not be set per instructions. The literature said to set cutoff at approximately 12 o'clock and set frequency to 19kv as necessary. This is what I did and assume that this was what was going on with my board. I started setting up my wire harness when I realized I did t have the right transformer. Soon to be remedied. I did et some monitor ox dimensions for my MH cabinet.
 
I read somewhere, I believe it was amplifone frequently asked questions that the Chinese flybacks were not capable of the 25kv needed for cutoff therefore could not be set per instructions. The literature said to set cutoff at approximately 12 o'clock and set frequency to 19kv as necessary. This is what I did and assume that this was what was going on with my board. I started setting up my wire harness when I realized I did t have the right transformer. Soon to be remedied. I did et some monitor ox dimensions for my MH cabinet.

I have made 3 x HV's using the cinelabs Flyback, and they all cutoff at 25KV

One has the Amplifone Focus block, and 2 have the WG6100 Focus Block, all 3 cut off

Could it be the second hand Block causing the non cutoff.

Anyway, if it doesn't reach 25KV during setup, there is no danger of it exceeding 25KV by itself, so no need for worry I guess
 
Focus block from original wells Gardner 6100. Not sure what's up. Will see if second board gives same results or what. I got the amplifone flyback from Bob Roberts. Focus block to be used will be from replacement WG6100 flyback. Should be the same as before but not sure about cheep Chinese parts.
 
Focus block from original wells Gardner 6100. Not sure what's up. Will see if second board gives same results or what. I got the amplifone flyback from Bob Roberts. Focus block to be used will be from replacement WG6100 flyback. Should be the same as before but not sure about cheep Chinese parts.

Mine are all chinese too
I am just curious as to why yours can't reach 25K, so I added it as a known (unresolved) issue

I would love to compare parts and voltages - side by side, but that would be a tough ask ;)

As I say, until we know differently, it could be the Focus block
 
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