Atari Firefox
- Thread starter Jodo
- Start date
A small but soul-destroying update. OK. It's not that bad
I've been checking resistance and voltage output on the two AR2's under the tuition of Mr Spicer, before I test under a dummy load; via a plug in resistor I've rigged up.
The factory, non-modded, AR2 is putting out 5v correctly from 'J7' but...the sense modded AR2 is outputting 14.3v from the 5v on J7
I've checked and double-checked this. Adjusting the 5v pot does nothing to the reading
EDIT: This may be how a sense modded AR2 is supposed to behave but how does the 14.3v translate to 5v to the game PCB stack?
Jodo2012-12-09 16:18:32
I've been checking resistance and voltage output on the two AR2's under the tuition of Mr Spicer, before I test under a dummy load; via a plug in resistor I've rigged up.
The factory, non-modded, AR2 is putting out 5v correctly from 'J7' but...the sense modded AR2 is outputting 14.3v from the 5v on J7
EDIT: This may be how a sense modded AR2 is supposed to behave but how does the 14.3v translate to 5v to the game PCB stack?
Jodo2012-12-09 16:18:32
hmmm, I never bother with the sense mod but I thought it just tied the +sense to +5v and the -sense to GND. I take it the input voltages to the AR2s are correct and in fact coming from the same power brick? The input voltage to the AR is 10.3 volts DC unregulated looking at the Star Wars schematic (in front of me as ever...) since it's unregulated it might be higher than 10.3 volts with no load, in which case maybe your input voltage is also currently your output voltage.
karlcdoe2012-12-10 00:09:46
karlcdoe2012-12-10 00:09:46
No, Karl's right, if done correctly then the sense mod just ties +sense to +5v and -sense to ground, thus feeding the LM305 with exactly what it outputs.
Whether that could even remotely possibly cause it to see 14.3v, I don't know, I'm too tired to think about that one at the moment but I've never heard of it.
Whether that could even remotely possibly cause it to see 14.3v, I don't know, I'm too tired to think about that one at the moment but I've never heard of it.
OK. Update time!
I've just tested the input to both AR2's (the 10.3v unreg) and both are getting 14.69v.
On the unmodded AR2 the 5v is outputting at 5.16v (with no load)
On the modded AR2 this looks to be taking the 14.69v and outputting it as 14.3v instead of 5v (with no load)
I've just tested the input to both AR2's (the 10.3v unreg) and both are getting 14.69v.
On the unmodded AR2 the 5v is outputting at 5.16v (with no load)
On the modded AR2 this looks to be taking the 14.69v and outputting it as 14.3v instead of 5v (with no load)
Well, based on your findings the modded AR2 needs some work then... I guess you have checked that it has been modded in the 'usual' way? There is at least one site a google away that should confirm that. If that's the case then you might want to consider checking Q3 (2N3055) transistor or you could send it off for repair
Time to get back onto this now the nice weather is here!
Over the past few weeks thanks to Alpha1, I've managed to score another complete Firefox board stack and 2 original Philips LD players.
Today I decided to test the boards.
Given the bad AR-II described in the previous updates I unboxed a spare I'd forgot I had (!) This AR-II was rebuilt by our very own Level42.
I dropped it into the cab, removing the suspected faulty AR-II for later inspection and connected everything back up. A visual inspection of the game boards revealed that this is a Sit-down NTSC PCB that has had the correct modifications carried out to make it compatible with the upright cab. The main PCB and Graphic PCBs were serial labelled 'URxxxx' anyway, so no issues there. All boards are very clean with no signs of corrosion or damage. The edge connectors are good with no sign of burn.
Before hooking the PCBs up, I powered up and checked the voltages were correct at the edge connector. With no load I was getting a little over 5v - good
The replacement AR-II appeared to do the trick.
I connected the PCBs up and fired up the cab a second time. To be honest I didn't expect anything; I believe Ol rescued these boards from a skip (!) I was pleasantly surprised to be met by Clint Eastwood saying "Boy is this a machine!". OK so the sample is playing too slow from memory but the key thing is, we have progress.
Next up:
I need to hook up a raster monitor I have and see what the screen is doing, and then get power to these LD players and check they spin up at least, before they go off to be fixed by another very cool member on here
Jodo2013-07-06 14:00:23
Over the past few weeks thanks to Alpha1, I've managed to score another complete Firefox board stack and 2 original Philips LD players.
Today I decided to test the boards.
Given the bad AR-II described in the previous updates I unboxed a spare I'd forgot I had (!) This AR-II was rebuilt by our very own Level42.
Before hooking the PCBs up, I powered up and checked the voltages were correct at the edge connector. With no load I was getting a little over 5v - good
I connected the PCBs up and fired up the cab a second time. To be honest I didn't expect anything; I believe Ol rescued these boards from a skip (!) I was pleasantly surprised to be met by Clint Eastwood saying "Boy is this a machine!". OK so the sample is playing too slow from memory but the key thing is, we have progress.
Next up:
I need to hook up a raster monitor I have and see what the screen is doing, and then get power to these LD players and check they spin up at least, before they go off to be fixed by another very cool member on here
Jodo2013-07-06 14:00:23
OK. Things just got interesting. There appears to be 2 sets of RGB GND Sync cables running into the monitor area. I've dropped a standard raster monitor in and have power but how am I supposed to hook up 2 sets of plugs - any ideas?
Mitchell Gant
Active member
There are two plugs for two monitor options that Atari could see.
So you have to choose the appropriate one for the monitor you are using
So you have to choose the appropriate one for the monitor you are using
P-Man said:
Hi Andy,
Yes - the manual identifies each cable's function, order in the plug and the wiring colour; this matches the plug in my original picture above perfectly:
What I can't get it to do is sync with this WG monitor I've got hooked up. I've tried both sets of sync (neg/pos) pins and also bridging H+V Neg sync but I cannot get the picture to sync correctly.
The game plays but there is 2 of everything and it appears stretched! See pics:
I'm missing the backgrounds as there is no LD hooked up.
Mitchell Gant
Active member
That image and the fact that you say the speech sample plays slowly makes me think it's either a graphics board clock fault or a clock/PLL fault on the NTSC board.
You should first check the 3.58MHz test point on the NTSC board and verify it is the correct frequency with a scope or frequency counter.
If not then you could try altering the PLL lock pot, but I've never seen it reduce the frequency, only increase it, for much squeaky voice fun.
If the clock is correct then it's a graphics fault plus a speech section fault too.
I'm chasing multiple faults on all my FF boards over the last few weeks. Looks like I'm gonna need a bigger test rig...
You should first check the 3.58MHz test point on the NTSC board and verify it is the correct frequency with a scope or frequency counter.
If not then you could try altering the PLL lock pot, but I've never seen it reduce the frequency, only increase it, for much squeaky voice fun.
If the clock is correct then it's a graphics fault plus a speech section fault too.
I'm chasing multiple faults on all my FF boards over the last few weeks. Looks like I'm gonna need a bigger test rig...
OK. More progress!
A *BIG* thanks to our very own Mitchell
Gant.
Neil was kind enough to loan me a Firefox NTSC PCB to connect up in my FF cab to see if:
a) The PCB stack I nabbed from Alpha1 checked out...
b) It solved the multiple images I was experiencing above...
b) It
solved the slow speech issue I mentioned above...
As if this wasn't already a really
generous thing to do to a guy he'd only met 2 hrs previous, Neil then made a
special trip to personally deliver his Dexter Beta / Raspberry PI setup on loan, so I
could play the cab to its full potential.
This is what happened when we flicked
the power on. I am so happy I can't begin to say how amazing it is to play on
an original cab after so many years
A *BIG* thanks to our very own Mitchell
Gant.
Neil was kind enough to loan me a Firefox NTSC PCB to connect up in my FF cab to see if:
a) The PCB stack I nabbed from Alpha1 checked out...
b) It solved the multiple images I was experiencing above...
b) It
solved the slow speech issue I mentioned above...
As if this wasn't already a really
generous thing to do to a guy he'd only met 2 hrs previous, Neil then made a
special trip to personally deliver his Dexter Beta / Raspberry PI setup on loan, so I
could play the cab to its full potential.
This is what happened when we flicked
the power on. I am so happy I can't begin to say how amazing it is to play on
an original cab after so many years
Mitchell Gant
Active member
Loaning the Dexter was purely a diversionary tactic to get into Jodo's lair with one very simple aim:
TO CHECK FOR A CAPE
HUNG ON HIS SPACE
HARRIER !!!!
Didn't spot one though, I think he hid it before I got there.
TO CHECK FOR A CAPE
HUNG ON HIS SPACE
HARRIER !!!!
Didn't spot one though, I think he hid it before I got there.
Awesome !!!
