Jump to content
Due to a large amount of spamers, accounts will now have to be approved by the Admins so please be patient. ×
IGNORED

Connecting an Arcade PCB to a CRT TV


Recommended Posts

Unfortunately I plugged the TV in, the red light came on, pushed the channel up button, the red light went dim then solid again.

I spent a couple of hours checking some of the transistors, diodes and caps etc with no luck.

 

Will grab another TV tomorrow and may come back to this one later and check voltages as per the manual and see what I come up with.

Edited by Kaizen
Link to comment
Share on other sites

  • Replies 129
  • Created
  • Last Reply

Top Posters In This Topic

Okay, the next TV I found was a JVC AV-21FT and has the same chassis and chips as the second one I modded.

This should be reasonably straight forward and I've tested this one out first.

 

Pv6VZTy.jpg

Edited by Kaizen
Link to comment
Share on other sites

Is the teletext chip IC821 installed? If so it will make it so much easier to understand the schematic.

 

 

I believe you will just need to remove R706, R707 and R718. Use them as injection points by twisting 680R or 750R together with 75R into the empty slots. Then blanking is 5V into the lifted leg (closest to micro controller) of R708 if you want hardwired RGB...

Link to comment
Share on other sites

Ok. You can possibly use the empty text chip header as your injection point.

 

 

Sent from my iPhone using Aussie Arcade

 

a49YfJ4.jpg

 

 

 

@Kaizen you seem to be lucky with the JVC sets so far, I had one that looked identical to the first one you modded but had a all in one jungl/micom with RGB inputs disabled within the chiphttps://www.aussiearcade.com/attachment.php?attachmentid=149309

 

 

Yeah it's definitely pot luck.

Link to comment
Share on other sites

Connecting an Arcade PCB to a CRT TV

 

Much of what I said still holds.

 

Remove the OSD ground resistors R706, R707 and R718.

 

Twist the 680 or 750 ohm resistors with 75s and solder the legs of the 680/750 into the empty pins 15,4 and 14 of IC371 header. The 75s legs go to ground, can use pins 6,7 and 8 of IC371 header.

 

Your RGB goes into the twisted legs sticking up.

 

Sent from my iPhone using Aussie Arcade

Link to comment
Share on other sites

For blanking take a 1K resistor, connect it to 5V and then to a switch if desired then to Y374 or the leg of R708 farthest from micom or the ungrounded pad of missing resistor R734 or the ungrounded leg of R374....

 

 

Sent from my iPhone using Aussie Arcade

Link to comment
Share on other sites

I didn't have any 680/750Ω resistors on hand and thought it would be good to be able to tweak the voltage if needed so I built a small board with 1kΩ trimmer pots (preset to 700Ω) and added a 1kΩ Sync resistor on it s well.

 

7NoQFrH.jpg

 

I injected the RGB into the locations as suggested but found that the ground pins 6/7/8 were floating. Link wire W013 was not populated (not shown on the schematic) so I added a link in at that location to tie pins 6/7/8 to ground.

 

g5l4S0m.jpg

 

ijUnYSd.jpg

 

I followed the front AV input to link W411, removed it and soldered the Sync in the through hole.

 

DlDWt8c.jpg

 

+5v was taken from the + of C708.

 

HkvWUxp.jpg

 

 

Then passed through a 1kΩ resistor and connected to the Base and Emitter pads of Q371.

 

U6y7Cfv.jpg

 

kpd84TW.jpg

 

The mod worked perfectly and the OSD overlays on top of the screen if adjustments are needed as seen in the first video.

The second video was taken with the lights off.

 

aIBYSww.jpg

 

 

 

The camera doesn't do it justice, looks much better in real life.

 

Thanks for you help with this @MarkOZLAD.

Edited by Kaizen
Link to comment
Share on other sites

Looks the goods. Should give you a good idea of how easy the OSD/External RGB Mux method can be to implement. IMO it is way easier than using a massive switch and you get the bonus of a useable OSD. Just have to know the method and then do a bit of study of the schematics to work out a neat way to implement.

 

 

Sent from my iPhone using Aussie Arcade

Link to comment
Share on other sites

I found this one a lot easier after already having done one on the same chassis, there's plenty of locations with through holes and if I spent a but more time looking over the board I probably could have found a way to run the blanking on the top side.

I'm really happy with the image it puts out and now have the motivation to finish the cocktail that's been sitting for over 12 months.

I have another two cabs waiting on monitors so I might have to start hitting kerbside collection again.

There's one more 21" TV of the right era left, I'll pull that out and mod it (if possible) when I get bored.

Link to comment
Share on other sites

I think this service manual should help you get into service menu.

 

https://data2.manualslib.com/pdf4/91/9052/905199-jvc/av14ftg2.pdf?494d0271e0c08f32e4724316c92001e5&take=binary

 

Page 14

 

Press the DISPLAY key and the PICTURE MODE key of the REMOTE CONTROL UNIT simultaneously. Then enter the SERVICE MENU mode as shown in Fig.1.

 

 

 

Sent from my iPhone using Aussie Arcade

Link to comment
Share on other sites

I have another two cabs waiting on monitors so I might have to start hitting kerbside collection again.

 

These mods are very cool. Very interesting too, thanks for the share.

 

I've been keeping my eyes open mate, there are not TV's out there anymore, just shitty broken LCD/Plasmas :(

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...