Frogger PCB issues

drbible

User
vacBacker
Feedback
2 (100%)
Credits
99CR
Anyone know what these 2 chips do on a frogger PCB. They are separate from the ROM board.
One has a broken pin - is there any way to replace the chip? Game has video issues (sound all good) so not even sure if thus is where the problem lies. Voltage thru all ROM board chips is fine. These 2 chips show much lower voltage though.
Any advice much appreciated as out of my depth.
Screenshot_20230124_130024_Gallery~2.jpg
Screenshot_20230124_130049_Gallery.jpg
 

bones

Active member
Feedback
15 (100%)
Credits
1,628CR
Yeah they're both eproms, looks like a galaxian bootleg type PCB. Should be easy to clean the leg up and solder a pin on it to see if it is your only problem. At the very least you could clean the leg up,pop it back in the socket and use the leg of a resistor to put in the broken pins socket and press it against the broken pins to see if the fault clears.
 

drbible

User
vacBacker
Feedback
2 (100%)
Credits
99CR
Thanks all. No idea what the board actually is - here's a pic of the whole board if anyone can identify.
I might just fork out for a new chip anyway.....where can I get one from and is it a straight swap over?
If these are the video chips then that's def where I need to clean. I use a fibreglass pen so expect more legs to break since they look quite worn.
Screenshot_20230124_143944_Gallery~2.jpg
 

bones

Active member
Feedback
15 (100%)
Credits
1,628CR
There's plenty of people on here who do this sort of thing,the problem I see is that there might be many different program versions out there and you will need the correct one. You might need to send those 2 eproms to whoever, so they can read and copy them. Hopefully somebody else could confirm my suspicions. Also I've not seen that type of connector for the main wiring before.
 

drbible

User
vacBacker
Feedback
2 (100%)
Credits
99CR
I know - the wiring is out there. There is a connector on the board but it's not cut out. I do have an original frogger I could put in and rewire but I'd quite like to get this set up working as is for some reason.
FYI not much difference with the broke pin replaced by a piece of resistor. Alsonfound a couple of broken legs visible on 7927A and another chip MB74LS04.
 

NivagSwerdna

Active member
Feedback
1 (100%)
Credits
849CR
Looks like Frog on Bootleg Galaxian.

If you Google EDM-28 (the marking top right) you get some hits.

Bodging a leg on might be the way to go. Looks like there is some sprite rendering.
 

drbible

User
vacBacker
Feedback
2 (100%)
Credits
99CR
Yes there's a scrap EDM-28 on ebay that I might offer £50 for and see what I get. Otherwise going to bodge the broken legs with solder and then give up.
Anyone think I could send this off for repair or is that wasting a repair servicers time?
 

bones

Active member
Feedback
15 (100%)
Credits
1,628CR
Unfortunately bootleg PCBs don't hold much value, meaning a repair would probably cost way more than it's worth. £50 for a scrap bootleg PCB is OTT as you'll just have 2 faulty boards and the chances of the eproms being for your frogger are remote. The 2 other broken legs you mentioned could possibly cause the issues. I reckon you should try sorting the 3 broken legs out first and see if anything changes and give it a proper check for any others.
I looked at a galaxian bootleg once and had to change over half the chips over a period of 3 days, so on an hourly rate he could have bought 3 working ones instead,but I did it FOC because it was a mate. Maybe if the legs don't sort your problem somebody knowledgeable might take it on or even part x it with cash for a working one.
 

bones

Active member
Feedback
15 (100%)
Credits
1,628CR
Forgot to say that the eprom sockets on these boards can cause problems too. It'll be worth gently pressing down on each one when it's powered up,sometimes the chips legs blacken or oxidise or the sockets springyness has gone meaning it barely grips the leg if at all.
 
Top