TTSH rev1 known issues

Here are some important Issues and Fixes from the first batch TTSH pcbs (delivered around March 2014)

other TTSH version known issues are described in the own project sites

update 01.October 2014 VCO2/VCO3 bleed fix

(page links/anchors)

1. pcb silkscreen failure for powersupply

2. Hum issue on Speaker and more
   
   

3. Noise "distorted"

4.   Clock bleed on VCO pitch    

5. wrong Silkscreen for matched pairs
   
   

6. wrong Silkscreen or polarity for Capaciator C20

7. TTSH known issues#VCO Bleed - Regulator

8. not all LEDs are working

9.  LED Dimming Fix 

10. TTSH known issues#VCO2-VCO3 Bleed fix

Solutions:

= tested

= untested

 FIX for pcb silkscreen failure for powersupply

cross one Ferrite on top pcb side - the ferrite on other pcb site (not shown here)

Open

other way:

FIX for Hum issue on Speaker:

Open

This Issue occurs by using the internal DC-DC Adapter,

FIX: short out the 10Ω resistor and the 100p capacitor in the PSU section. E.g. just make a small bridge between the pad close to 10Ω and 100p as in the attached picture.

further use RG174 cables or shielded microphone cable for offboard wiring.

make Attention on resistor 470R on frontside - see here (LEDs dont work)

Open

FIX for distorted Noise.

Option A: the easiest way is the usage of a BC337-16 with folllowing orientation, there´s no need for addional parts.

Open

Option B (from nordcore)

leave out the 2n5172 - use a bc337-40, - bend right leg to top, solder a 10K resistor in series to the 1uF cap.

see here to choose the correct BC337: https://www.muffwiggler.com/forum/viewtopic.php?p=1558920&highlight=#1 558920

Open

Option C: (same like Option B)

other working solution howto connect a 10K resistor to the cap (after soldering, use shrinktube for cap and resistor housing )

leave out the 2n5172 - use a bc337

Open

FIX for Clock bleed on VCO pitch