Video frequency not supported

[Dopy25]

Does this mean the 3 monitors I tried it with are incompatible, or I have the wrong pins for color? Monochrome works on each TV if I ground out the monochrome detect, but when I be remove the detect, it shows nothing, but one of the monitors said this:

[TGB1718]

Most modern monitors will not do Medium/low resolution, there's a thread on those that people have found to work

 

 

[Dopy25]

38 minutes ago, TGB1718 said:

Most modern monitors will not do Medium/low resolution, there's a thread on those that people have found to work

 

 

Oh for sure. I've read that thread as well. My only concern is whether or not I have wired the cable correctly. The error I get, is that what one would see if the monitor did not support the right frequency, or could it be that I have the cable wired incorrectly?

 

EDIT:

I think I may know my problem. I made a cable for mono, and just disconnected mono dete4ct, thinking it would show color. But after looking a bit more it seems the cable I made connects all 3 color wires to one. I am going to wire a new cable for color only and try again before moving forward.

Edited June 28, 2022 by Dopy25

[Tillek]

If whatever you're thinking doesn't work for you, please consider providing a little more information... like what kind of monitors (brand/model) you're trying to use.

 

Might help.

 

[djglish]

There area proper pinouts for both color and mono available online.  I built a switchbox years ago that let me go from one to the other.  That was when I had a monitor that would sync to the lower 15mHz setting. 

[Dopy25]

26 minutes ago, Tillek said:

If whatever you're thinking doesn't work for you, please consider providing a little more information... like what kind of monitors (brand/model) you're trying to use.

 

Might help.

 

Fair enough. Will post regardless of if it works. I know one was ASUS, one was Dell, and the third (the one in the pic) was a viewsonic. I can get model numbers later as well. I really think it's because I did not separate the color lines because the instructions for mono have them together. I don't know why I assumed all I had to do was disconnect the mono detect. I think I was half asleep and in a rush to get to bed.

 

I know that basically all monitors are different, but was wondering if it was possible to detect the right frequency but still identify it as being out of range if the wiring was correct. Again, at this point because I have had more coffee, I understand that I had the color lines merged and it should not work at all anyway. I went from mono out on the ST to RGB on the vga. One line to 3. I didn't even have the RGB from the ST wired in.

 

 

9 minutes ago, djglish said:

There area proper pinouts for both color and mono available online.  I built a switchbox years ago that let me go from one to the other.  That was when I had a monitor that would sync to the lower 15mHz setting. 

I realized this after posting. I will check when I get a chance using the correct pinout. 

Edited June 28, 2022 by Dopy25

[Tillek]

I don't know the link off hand... but there is a list of known 15khz monitors... if you're trying to wire up a color cable for med/low res, it's not likely to work without some kind of scan converter.  That said, it's probably cheaper to just get one of the monitors that are known to be good for it.

 

I spent quite a bit buying monitors from thrift shops trying to see if I could find any that would work... I ended up with a ton of monitors I ended up donating back to the thrift shops.

[Dopy25]

6 minutes ago, Tillek said:

I don't know the link off hand... but there is a list of known 15khz monitors... if you're trying to wire up a color cable for med/low res, it's not likely to work without some kind of scan converter.  That said, it's probably cheaper to just get one of the monitors that are known to be good for it.

 

I spent quite a bit buying monitors from thrift shops trying to see if I could find any that would work... I ended up with a ton of monitors I ended up donating back to the thrift shops.

This one? 

http://15khz.wikidot.com/

 

I'm not sure how updated it is but I do have a few monitors around the house I wanted to try. I don't think any are on that list, but it could be possible since that is a whitelist of known working.

[Tillek]

Oh, yeah... by all means try if you like... you never know what you'll find... After all, that's how they found that dell monitor that worked.  I'm just saying the results you're getting are kind of what would be expected... so once you correct the cable, it wouldn't be surprising if you still got that result.

 

 

[+Stephen]

Yeah - as stated by others - 15.75kHz won't display on most modern monitors wanting 31kHz horizontal refresh rate.  Frequency not supported is exactly the error you would get from that.

[Dopy25]

Was definitely a combination of the cable and monitor choice. BUT one of my monitors did work perfectly once it had a valid feed. 

The one that said out of frequency still didn't work, and I didn't pull out an adapter for the Dell monitor I have as it does not have a VGA input, but the Asus monitor works great! 

I have access to color modes now.

 

[Tillek]

Great find.  That one didn't seem to be on the list (at least not the ones I just checked).

 

Does it do both low and med without missing lines or jailbars?

 

 

 

[Dopy25]

1 hour ago, Tillek said:

Great find.  That one didn't seem to be on the list (at least not the ones I just checked).

 

Does it do both low and med without missing lines or jailbars?

I do not see any missing elements and it seems to switch fine between low/med. Honestly it seems really smooth to me. Is there a utility I can run to find out? I just got my sd card floppy/HDD adapter in the mail today and am setting it up now.

[Tillek]

Nah... the eyes are fine... On some monitors you'll see missing vertical lines (like if you look at the drive icons, you will be able to tell that they are missing lines as the letters look off) or you'll have obvious other artifacts... Some will work fine in medium and not in low, or vice-versa.....

 

But it's really just how it looks to the eyes.

 

Another thing to note (not specifically for your case, but just to put it out there) some monitors will only support certain frequencies with certain inputs.  Like that Dell monitor mentioned in that thread.  If you hook it up to VGA, it's all good... however, if you take that VGA output, convert it to HDMI and then try to use that same monitor's HDMI (without any kind of scan converter) it won't work, because only the VGA input can handle the 15khz.

 

So just something to keep in mind for those "trying this at home".  In my case, I was trying to hook up 2 ST's and 2 A8's through an HDMI switch.