Text 214, 94 rader
Skriven 2005-01-30 06:40:06 av James Bradley (1:134/77.0)
    Kommentar till text 213 av Roy J. Tellason (1:270/615.0)
Ärende: Monitors nee-But it's ec
================================
01-29-05  20:06, Roy J. Tellason told James Bradley about Monitors nee-But it's
ec

 Well, how do, Roy?

 RJT> I'm thinking that it's probably some power-handling 
 RJT> component that's gone bad, and perhaps some electrolytics 
 RJT> as well.  Gotta get an ESR tester together one of these 
 RJT> days.
 
 JB> ESR? I hope you aren't depending on an Extra Sensory Receptors. <G>

 RJT> Equivalent Series Resistance,  a common problem with 
 RJT> capacitors,  particularly electrolytics...

So it's the plate-plate insulating material that provides the component of pure
resitance? ... Oh for just the degridation, and you need to passivly test it?
<Skatching head>
 JB> ...I'm sure this is only NTSC, but maybe PAL too, but I doubt it. I
 RJT> Hm.  Let me know what it turns out to be,  just out of curiosity.
 
 JB> Turns out to be a "T.V. Post Marker/Sweep Generator" Model IG-57A.

 RJT> That's not a pattern generator,  it's one that's used for alignment of

I know that now. <D> Since I shoved it in the rack - some half dozen years ago
- that's the best recollection of the unit I came up with. On the front it has
an input for IF, and two channels of influence. (Yada-yada-yada...) I likely
noted that it had a BNC on the front labeled IF, thought it was an output, then
found a place for it on a shelf.

When I buy at auction, I try to go for the quantity deal. That box came with
the hospital's TV distribution system. Got a BIG pile of stuff from that one!

Say, since you brought it up... <-; I purchased at gov. auction a V-mA meter
that displays via a swinging mirror assembly. Any ideas what makes these work?
 RJT> the IF  stages.  The "sweep" refers to a frequency modulation of
 RJT> the output,  the modulation also being used to provide 
 RJT> horizontal deflection input to a scope, and thereby 
 RJT> generating a response curve.  The "marker" part refers to 
 RJT> generating a slight intensity variation on the curve so you 
 RJT> know where certain frequencies of interest are.  In the 
 RJT> years that I spent doing tv repair,  I could never quite 
 RJT> justify the cost of such an instrument.

That's why the local hospital board absorbed the cost, and I got it in a
two-fer. <L-like a maniac) Now I need more storage space. <cower>
 RJT> Sometimes,  with real early stuff,  the sweep generator and 
 RJT> marker generator were separate items.
 
You know, beside the wonkey pictures you can make with the unit, it would be
good for little else than to tax or deplete a subsystem?
 RJT> I wonder how difficult it would be to take an old 386 or 
 RJT> something and stick an extra (!) video card in it,  use it 
 RJT> for a generator?  Linux would support this,  no doubt.  I 
 RJT> know it will support more than one sound card... 
 
 JB> The kernel would have to be an older ones, no? All I've seen
 JB> nowadays, is a i586, or above.

 RJT> Not a problem,  mostly.  The tricky part would be to find a video card
 RJT> to use  for generating that output that would have sufficient 
 RJT> flexibility to allow for a wide range of frequencies that 
 RJT> could be tweaked,  rather than a small number of discrete 
 RJT> ones to select from -- this is what one of my monitors here 
 RJT> can deal with,  and I don't recall the specifics on any of 
 RJT> the cards offhand.  I know that the one (ISA) card I have 

Capt. solder runs an ISA card! Eveybody... <LOL>
 RJT> in this box has several of those little oscillator modules
 RJT> on it,  and seems to generate a whole lot more in the way 
 RJT> of tv interference than the one I was using before that 
 RJT> died.  My antenna consists of a bit of wire,  and I guess 
 RJT> those modules radiate enough hash,  that mixes,  that it 
 RJT> messes things up.  Good thing tv reception in here isn't 
 RJT> that high a priority with me.

I think it was an old Osbourn lug-able, that I pulled a Herc. TTL/EGA (If
that's the one that used a low density D-plug?) card out of. That I could use
for test paturns. It's a full length ISA board, but maybe only able to draw two
colours.

Ya... any day now. <-;

Me, I just plugged the capture card into a 21" monitor. That sheilded cable
comes in handy to take the reception elsewhere.


... 'am' B'ad'

___ Blue Wave/QWK v2.20

--- Maximus 3.01
 * Origin: -=-= Calgary Organization (403) 242-3221 (1:134/77)