15, 25, 31khz monitor?

[Ummon]

I remember some here saying there's a switch of some kind, or jumper?, on some monitors that change the scan rate accepted. Not the best image, but what should I be looking for here?

[grantspain]

3 ways multi sync switch
jumper plug on the main chassis,you will find two connections marked low/high-this will be 15/25 only

on the control board there will be 2 switches which produce different options like on the early nanao tri sync

most tri sync will auto range to the correct signal,some have a signal impedence switch on the control board such as the rodotron and wei ya

some dual sync 15/25 are auto sync as well

normally a tri sync will have a vga connector as well as a 5/6 pin rgb connector

[Ummon]

I didn't see any of those things you mentioned. However, after some testing, I found it is an autosync, apparently 15/25.