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18 hours ago, Mikebloke said:

Are we all looking for slot machine, poker and checkers??? :D

And a few others. ?

 

What I really need is someone to do a refurb on my machine, and fix my button 2- but since I had to replace the TV just the other day, that's not happening for awhile anyway.

As I posted in the "Fairchild Channel F Fan Page" Facebook group ( https://www.facebook.com/groups/1180282045468082/?ref=group_header ) I have tested eight #4 carts, earliest (1377) and last ones I have (7839). Works the same, you get to the end of the sequence but no message and any keypress after that resets. 

 

I'll try the rest of them as well but I don't have any high hopes. The code is fine but the environment it's in doesn't let it execute properly. It would have (it does) worked just fine in a development cartridge with eproms and a memory interface.

 

 

I'm dusting off my Channel F after about 10 years of non-use but I can't remember what is needed to connect it to the TV.  I played it on my current old projection TV back then (analog antenna input) so I know I've done it before, but there is that odd RCA plug in the back.  Can someone remind me of what I need to hook it up to my TV?   Thanks!     

Update:  Okay I dug up one of my 'TV/game' rf boxes,  switched it to 'game', ran an rca cord from its 'GAME' socket to the Channel F, then a coax plug connected to the TV's analog antenna input, the wire splitting into the 'TV' screws on the rf box.  But all I get is this when I turn it on.  This does not look good, I hope I'm not screwed.  Can't see any response from the buttons, this is with no cart inserted.  Boy I sure hope I just have this input hooked up wrong...

67675860_2355016567948256_2970387076832296960_n.jpg

Edited by frenchmarky

Update #2: I reseated the one socketed chip in the Ch F but no difference.  Then I noticed that if the game has been off for a minute or two, then it DOES begin to load either from internal memory or from my carts (backgammon in pic below), buttons work etc., but in about 10 or 20 seconds it freezes up with random junk slowly filling up the screen.  If I turn it off and back on the freeze is immediate, it's as if something gets to a certain temp very quickly and then it won't load.  I think I might be using the wrong type of RCA cord too because the video is still very grainy but... anybody have suggestions on this freezing up thing, like maybe the two big capacitors drying out could cause it (I hope because I could handle that!)  Thanks!

68353066_1254355728079176_7400370750000988160_n.jpg

You could have a short somewhere overloading the voltage regulator or perhaps there's poor thermal contact which causes overheat. 

The socketed chips are prone to oxidation, there's silver in them, they turn black - at least on the upper part of the pins. 

There's another guy with the same kind of problem. He has swapped regulators and electrolytic caps but no luck so far. 

 

I had a problem like that in a European version, turns out a tantal capacitor was shorted, they're egg shaped, blue, green or beige usually... Perhaps there's one under the RF box.

 

Regarding your other problem, there's an adapter you can get that fits directly between the TV and the antenna cable (eBay) so you don't need a switch box. Swapping the cable may also help. 

Installing a composite mod will give you the best image of course. But, no idea as long as it's not working properly. 

  • Like 1

Whew, I did a better job of reseating that chip again and now the unit is working 100% so I will check the chip and socket for corrosion.  As for the picture quality, it can gradually vary from bad with interference to fantastic if I move the cables around so I will dig up some better ones.  I do have some standard RF boxes for my antique TV sets but they don't have an RCA socket for the Ch F wire.  Would it work right if I use a coax-to-rca adapter plug between the Ch F and the RF box?  Or just cut the end of the RCA cord that goes to the RF box and attach the wires directly to the antenna lugs on the box instead?  Thanks

Edited by frenchmarky

I experimented a little and found (with my particular 20-year-old projection TV anyway) that with the Ch F's RF wire spliced directly to the coax connector going to the TV (no RF/antenna or switch box) I get a beautiful picture, zero interference now.

68392564_2100178423427146_1814090312046346240_n.jpg

  • Like 1
On 8/8/2019 at 11:51 AM, e5frog said:

I succeeded in composite modding my Luxor VES

Inspired by your progress, I took a closer look at my own mess of wires and immediately discovered that output 75R resistors on the proto board did not work, being short circuited by unfortunate track pattern on the board's bottom. I have no idea why I did not pay attention when I was soldering these. As the result, luma was working without proper line termination more or less okay, but chroma has been distorted savagely.

 

Now everything looks much better. I fitted S-Video socket on the rear part of VES case. Here's the picture on an old LCD TV with a lousy S-Video cable, hence the ghosting.

 

image.thumb.png.7af0699c1d61472a89f17beaff561d78.png

10 hours ago, e5frog said:

@tnt23

Looking good, show us your hookup / schematic. 
Does s-video get rid of the checkered flicker along the side of the graphics? 

The schematic is mostly copied from TI datasheet:

THS7314.png.87c4d107656999cc8a98ced39b8b114a.png

 

On VES, took color signal from C28 to pin 3 of THS7314, and sync from 'VIDEO SHT 1' point to pin 2 of THS7314 via 4K7 pots (not shown). Used those pots to set the voltage swing of signals on S-Video connector to ~1Vpp.

image.png.d1d47d00d9c2e995961d2a413d7a3334.png

 

Did not register any checkered flicker, but that's probably because I was more obsessed with color ghosting. Will post more closeups.

Edited by tnt23

I knew it was too good to be true, my Ch F played solid all yesterday and today after I reseated the socketed chip as I mentioned above, now I have this permanent dashed line going across the screen.  The carts and internal games still play okay but reseating the chip one more time (the pins are very clean and shiny) did not help with this dashed line.  This is really depressing.  Any suggestions?   Thanks

68674308_396888697687767_7142078933012316160_n.jpg

@tnt23 The color signal on s-video is not 1Vp-p, it's 0.3Vp-p IIRC. When running a C64 on LCA it has 1Vp-p on Chroma, that's what the C= monitor wants. So when using s-video signal has to be lowered or you'll get various artifacts.

So did you mean 1Vp-p from VES or is that signal level on the connector? 

 

@frenchmarky That's an odd one, problems with VRAM usually shows as vertical lines. Probably something before that. As you've had socket problems, perhaps it's time to swap sockets. 

@e5frog I have tuned the pots to set 1Vpp on S-Video connector pins, after the THS7314. Without lowering input signals to THS7314 its outputs went to good 2 or 3 volts swing.

Perhaps I should indeed tweak luma down to 0.3Vpp, just left it where the colors on that old LCD telly seemed all right to me :)

1 hour ago, e5frog said:
1 hour ago, e5frog said:

@e5frog That's an odd one, problems with VRAM usually shows as vertical lines. Probably something before that. As you've had socket problems, perhaps it's time to swap sockets. 

Next I tried pulling that chip *again* and cleaning any possible oxide off the pins, also swapped the paired 77xx and 78xx chips with each other (the only other socketed chips).  Zero change, dashed line still there.  Sockets look okay.  If this was just one dirty pin connection that was wasn't a problem a few days ago, I'd think all this reseating would have shown some change.  I have the feeling I'm going to need to dig up another unit.  :(

 

 

More pictures taken on PVM monitor:

20190813_210647.thumb.png.dcf740cf87ac628f1c0e42f3be06fe26.png 20190813_210736.thumb.png.7aa3dd97d912caec65e47252c7387a55.png

Color smear on vertical lines is a bit annoying. I will take another round of color taming, just need more courage to again dismantle the case and handle those deteriorating ribbon cables.

 

S-Video socket fitted on back of VES case:

20190813_210540.thumb.png.f9ede2dae55d3e7d1740068b3defd45e.png

Looks good, clear as a day but with some color artifacts.

I prefer using a connector on a cable and let it hang a couple of inches from where the antenna cable was - so mod can be reversed if needed. 
If you want to be able to control the volume it needs audio out as well...

59 minutes ago, e5frog said:

I prefer using a connector on a cable and let it hang a couple of inches from where the antenna cable was - so mod can be reversed if needed. 
If you want to be able to control the volume it needs audio out as well...

Connector on a wire is good idea, will consider this for future mods. It's a shame sound cannot be squeezed in S-Video, but then there are SCART connectors.

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