Burford Electronics Robot ring modulator RARE!

Rare and VERY cool pedal made by Alan Exley under the now defunct Burford Electronics name.
Mode 3 is like a step-sequence/tremolo kind of deal that I love, check out samples on Youtube.
It´s very musical for a ringmod pedal, most of them I think just makes noise, but this one makes music!

From effectsdatabase.com:

Feed your guitar through this device and you will get the guitar sounds mixed with the sum and the difference between the oscillator frequencies, producing 'metallic' overtones to your guitar and various strange techno sounds,depending on where the oscillator pitch is set.

What were ring modulators used on? If you listen to the guitar solo on the track Paranoid, by Black Sabbath, you will hear pure distortion on one side and ring modulation on the other. The stereo image sound quite weird. I'm quite sure it's been used on many things. Another classic example is on the Dr. Who theme. This device is great for playing riffs, creating loops, and other weird phrases.

It's features are:

• It has 2 controls, modulation and oscillator:
  • The modulation adjusts the mix of the dry signal to be effected.
  • The oscillator controls the pitch of the oscillator tone.
• It has 2 switches, one is accent, the other is range:
  • The accent adds another feature to the oscillation,which gives a slightly different character to the sound.
  • The range switch has three ranges:
    • 1 is the upper band [easier to tune to higher frequencies].
    • 2 is the upper and lower band.
    • 3 is the sub band, this gives low-fi tremelo type sounds [which can be quite 'nasty'], also there tends to be a 'click', almost like interferance from the oscillator, with the accent on you can get some bizarre trance type sounds by playing with or against the beats that are going on,all you need is root note and octave. It also sounds different if you play against the bridge.
• It has two jack sockets in and out.
• 9 volt battery or power supply negative center.
• It has true bypass.