Monthly Archives ⇒ February 2016

Modified servos

· daryl

This time I have upgraded to metal geared servos however they are still locked to +/- 90 degees and so they need modifying for continuous rotation.

IMG_20160219_132224 (Medium)

Here I am using 2.2k ohm 0.1% tolerance smt resistors to replace the potentiometer and trick the servo into thinking it’s locked in one postion.

IMG_20160219_165915 (Medium)Last time I used some random through hole resistors I had lying around and when it came to trimming the servos there was a lot of drift, far more than I could correct for, so this shall be a big improvement.

IMG_20160219_173252 (Medium)Tiny!

Mains cable and capacitor replacement

· daryl

Before plugging in and testing this radio I replaced some choice components to improve the safety and reduce the chance of damage to other parts of the radio.

The original mains cable was the old twin core single insulation type and had become cracked and hard.

The capacitors replaced were the mains line-to-line cap, aerial-to-chassis earth and the audio output capacitor.

IMG_20160205_180616 (Medium)

IMG_20160205_183319 (Medium)

Stella ST105U

· daryl

This is my first project in the world of valve based equipment and I’m very excited to be working on it.

IMG_20160201_161832 (Medium)

I bought it as a non running chassis from eBay but it seemed to be relatively complete, missing only the outer body. This won’t be a problem as you will see since I intend to laser cut a perspex case for it.