• Please review our updated Terms and Rules here
  • Exhibitor application for VCF West 2022 is now open! If you are interested in exhibiting, please fill out the form here.

New Epson QX-10 - no monitor

david__schmidt

Veteran Member
Joined
Jun 5, 2007
Messages
719
Location
Southeast US
I've taken delivery of a QX-10 computer and keyboard. No monitor, though. I have lots of nice references to the pinout, such as this:
http://fjkraan.home.xs4all.nl/comp/divcomp/qx10.html
Code:
 7-pin    8-pin
monitor   QX-10     function    wire color (original)
-------   -----     --------    ----------
 1 ------- 8        video       shielded wire
 2 ------- 5        v. sync     grey
 3 ------- 4        h. sync     red
 4 ------- 1        +12 V       brown
 5 ------- 2        sync gnd    green
 6 ------- 7        video gnd   shield
 7                  none
           3        none
           6        none
... but I'm a bit ham-fisted when it comes to video. What kind of monitor should I pull out? What will this drive? I have primarily Apple II and Commodore monitors available to me, plus the usual compliment of VGA-junk. I think my NEC Multisync got ditched in the last house move, so one really good choice is gone.
 

david__schmidt

Veteran Member
Joined
Jun 5, 2007
Messages
719
Location
Southeast US
Thanks, guys - those are both great resources. I will probably dork around with a B&W composite monitor and see if anything discernible comes through... I imagine tying the 'video' and one or both of the sync lines together might do it.

Edit: Nope, not composite. It must be that IBM-PC monochrome... short on time, I went ahead and ordered a monitor from notebooksupplies.com.
 
Last edited:

fjkraan

Experienced Member
Joined
Jul 30, 2003
Messages
113
Location
Netherlands
An IBM Monochrome monitor is not going to work. The QX-10 (assuming with the standard monochrome graphics card) has special sync frequencies: 19.3 kHz horizontal, 45.8 Hz vertical. The latter is probably out of range of most monitors, maybe except original Nec Multisyncs.

Fred Jan
 

Chuck(G)

25k Member
Joined
Jan 11, 2007
Messages
39,097
Location
Pacific Northwest, USA
The 5151 is pretty forgiving regarding horizontal scanning frequencies and might just be tweaked into accepting 46Hz as a vertical scan rate instead of 50Hz. There is a "vertical hold" control somewhere on the monitor (I don't recall if it's an on-board pot or an externally-accessible on) that just might get you there.
 

david__schmidt

Veteran Member
Joined
Jun 5, 2007
Messages
719
Location
Southeast US
Ok, monitor just arrived (yes it took that long). Does it really run on 12v from the computer cable? No power cord?

I have to wire up a cable after all... notebooksupplies.com had held up my order all this time because they were scrounging around for a cable, but couldn't find one. I finally told them to keep the money and just send the monitor. Only one left in stock... I didn't want to risk mine going missing.
 

tezza

Veteran Member
Joined
Oct 1, 2007
Messages
4,709
Location
New Zealand
Yes, all the power comes from the computer. Most unusual but it makes for a lighter monitor!

Tez
 

david__schmidt

Veteran Member
Joined
Jun 5, 2007
Messages
719
Location
Southeast US
Ok, perfect. I've got it apart and will install a DE9 - no 7-pin dins in my parts bin tonight.

[Later...]

The analog board gets its requisite 12v power, and I can feel the semiconductor-looking thing on a heat sink warming up. There's a power transistor-looking thing on the other side of the board also on a heat sink that is stone cold. I get no light of any sort out of either end of the CRT. I booted what is probably a Valdocs disk, and I expect it probably put some words out on the wire. Even swinging the brightness back and forth from stop to stop didn't reveal any photons in the CRT. The fuse is good. Is there anything super-obvious I might be missing? Is it fishy that the power transistor on a heat sink is cold?

[Much later...]

Stepping through the SAMS computerfax as best I can without a scope, it looks like the high voltage side of the house is not running. Good for my safety, bad for picture. Not due to the overvolt shutdown circuit, either - just not running. Could be my cable is miswired if it requires a sync signal from the computer to fire up. I was careful, but I went through two wire color scheme changes before it was all over [connector inside the monitor, then connector in the cable], so anything is possible. I may get desperate and hardwire a cable in and eschew fancy connectors.

[Last entry...]

Turns out a DIN-5 fits the socket on the monitor, and we really only need the upper 5 connections anyway. Got that all wired up and triple checked, and still no go. So I just ordered the last monitor notebook supplies said they had, and we'll see how that one goes.
 
Last edited:
Top