I need to reset a Aiko STB255 Standard Definition Set Top Box to factory settings. I have no manual. Could someone with a manual give me the steps to take. It was working fine but I tried to tune it to another TV and stuffed up somewhere. Now when I turn it on, it flashes the Logo and then turns blank.

moved you to TV , out of computer repair help.
this is what it is :

SP-110 HD is an innovative and feature-rich high definition Set-Top-Box, specifically designed for deployment in IPTV and Video-On-Demand Infrastructures.
why not call your SET TO BOX MAKER HERE. (1st google hit)
and ask
https://setplex.com/en/stb.html#

review your resolution setting and maybe there miss the set up..

You need a good set top box, either Hi definition or standard Pal, to make any CRT Television work. These days, non digital TV do work well but they no longer accept analog signals, but when connected to a set top box that receives digital signals, the box converts the digitals signals to analo and sends then to the RCA inputs of your TV and not via an antenna connected to the set top box and the TV.

http://www.awa.com.au/AIKO---Set-Top-Box/default.aspx
You can download the manual here. The factory reset is within. If you don't find it, let us know I will tell you how. Best to look for yourself as your set top is a diff one than mine and I want to be sure.

It's a standard definition set top box for high definition channels, I'm an idiot for buying it too

As the manual says "please make sure your TV set can support Progressive format before you select YPbPr Mode or you will can not see picture on TVset" (sic).

To get back from a blank screen:
1 unplug the STB to reset the menu positions to default (because you will be making menu selections blind)
2 plug unit back in and turn it on and use the remote to press in order:
Menu (TV sound will be muted because the menu is now displayed, even though you cannot see it)
Down
Down
Enter
Down
Enter
Down
Down
Down
Right (or Left)
You should then get a picture. Leave the picture setting at CVBS (and don't touch it again lol)
For visual cues on what you are trying to do, look at page 8 of the manual.

Connect video cable to Y: port. You will see all the menu again. change Video output back to CVBS. (I did the same thing, when i connect VGA cable to y(Green coloured port picture was blued but after few attempts i got clear picture)

Hiya Margy,
I know your query was 6 months ago,but I had a similar problem with connecting an Aiko SD set top box to our second older tv set & after 3 months only recently found the solution!
Our problem? When connected the tv picture went green! Nobody,including Tandy staff,knew what to do! (We also have an Aiko STB connected to our newer tv and it worked fine from day one.)
Anyway,it took 3 months but I finally worked it out.
Our problem was settings on the TV,NOT the STB.
Go to your TV's COLOR settings,pick a setting called 'COLOR SYSTEM' and change from 'ntsc' or 'pal'(depending on what country you're in) to AUTO.
It isn't enough to change the tv system on the STB's SETUP menu,or to change it on the TV's SYSTEM settings,you have to change it in the TV's COLOUR settings as well. Change colour system to 'auto' and see if that helps.(And of course,change all system settings on both the tv & the STB to AUTO or the right system for your country if you haven't done so) Hope this helps! Good luck!

I got AIKO STB 255 and it wont find any UHF channels i'm in Adelaide why is this so ?

Loss of sound is often a SCART connection problem. Check that the SCARTS are pushed in securely. Or if the SCART is old, it may be faulty. Try a newer one, or one that you know is definitely ok.