TTSH Sample and Hold, Internal Clock, Analog Switch and Amplifiers Done

May 9, 2015

TTSH Sample and Hold, Internal Clock, Analog Switch and Amplifiers Done

Earlier this week I've finished the Sample&Hold, Internal Clock and Analog Switch part:

Main Board, Sample&Hold, Internal Clock and Analog Switch CompletedComponent side, jacks and sliders still missing.

The 1.5µF electrolytic capacitor (bright blue) at the bottom wasn't available with Mouser, but luckily I had a few of these from the past. Then I had made a little mistake: Soldered in a 10Ω resistor instead of a 100Ω one (near the 1.5µF capacitor, in vertical position). I only noticed when a 10Ω resistor was missing for the next section, the amplifiers part. Removing the vertically positioned resistor and putting back in the correct one was not that easy.

[Update] Then only later I detected that the analog switch was not working correctly. Channel A was always on. I had overlooked to solder one side of a 3.3MΩ resistor that controls one of the 2N5172 transistors, which actually can be clearly seen in the top-left corner of the above image. The fix was thus easy, luckily.

Main Board, Sample&Hold, Internal Clock and Analog Switch CompletedBack side, jacks and sliders still missing.

And thus also the amplifiers part was finished: