🚀 go-pugleaf

From article <3600@hplabsz.HPL.HP.COM>, by dleigh@hplabsz.HPL.HP.COM (Darren Leigh):
> In article <3593@hplabsz.HPL.HP.COM> dleigh@hplabs.hp.com (Darren Leigh) writes:
>>I just bought an AmiGen genlock for my B2000 and and the flicker-fixer
>>doesn't seem to like it.  When I attach the AmiGen (whether I have the
>>video in/out connected to signals or not) the video output of the FF
>>seems to lose sync and gets really trashed.  Is this normal?  Is it
>>somehow avoidable or fixable?  Any help will be appreciated.
> 
> After reading a couple of e-mail responses I guess I wasn't very clear
> with my original message.
> 
> I don't have the AmiGen hooked up to the flicker-fixer output.  The
> flicker-fixer output is connected to a multisync monitor.  The AmiGen
> is hooked to the regular Amiga video connector.  The NTSC video output
> from the AmiGen looks OK, but the flicker-fixer output on the
> multisync is really hashed up.  This occurs whether or not there is a
> video-in signal connected to the AmiGen.  I guess the flicker-fixer
> doesn't like the Amiga genlock mode.  I really wish there were a fix
> or workaround for this, though.

This isn't much help in solving the problem, but it does explain it a
bit. Check page 8 of the flickerFixer's manual (I'm NOT gonna say RTFM,
honest, I won't! :-) 

"Any device that uses the genlocking capabilities of the Amiga cannot be
used simultaneously with the flickerFixer. The monitor connected to the
flickerFixer should be turned off while a genlocking device is attached
to the 23-pin video connector."

My guess would be that the problem is because Amiga genlocks substitute
their own clock for the system clock, and the flickerFixer can't
tolerate anything but the stock system clock.


I can offer one hint to anyone that has problems with "crawlies" on high
contrast images. The worst case is alternating dots of different colors,
like the test pattern that comes on the flickerFixer disk. 

Mine started having crawlies for a minute or so until it warmed up a bit.
This started after dragging my system out to a local university computer
show in the middle of winter, so the extreme temperatures probably over-
stressed the chip. The warm-up time gradually lengthened over several
months, until it took about 10-15 minutes before the crawlies
disappeared. Then they stopped going away completely. Tweaking the pot
on the back of the card had no effect, but tweaking the trimmer cap on
the board helped some. What cured it completely was touching the trimmer
cap with my finger. Since I don't type too well one-handed, I looked for
a more permanent fix. Swapping values of the cap that's paralled with
the trimmer changed thing for the worse. As a last resort, I decided to
try swapping some chips. With no schematics, and the board long out of
warranty, I decided to start with the obvious before sending it in for
service. The trimmer cap & pot are tied to a Phase Locked Loop IC,
(NE564). I got a couple of them (about $1.20 each), pulled the old chip,
and installed a socket (you could cause some REAL damage here if you
don't have some experience with desoldering ICs). The first chip showed
no change. After much tweaking and despair, I tried the other PLL.
SUCCESS!! A few tweaks, and it worked perfectly. 

So there you have a completely unauthorized way of voiding your
warranty. If you smoke something trying this, I never wrote this
article!

-- 
Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
Here: utah-cs!esunix!blgardne   {ucbvax,allegra,decvax}!decwrl!esunix!blgardne
There: uunet!iconsys!caeco!i-core!worsel!blaine  (My Amiga running uucp)
"Nobody will ever need more than 64K."    "Nobody needs multitasking on a PC."