Quantity: 1
Description: Dual Tellun Lag Processor in a Bridechamber panel.
The project is built on two MUUB-4 prototyping boards, stacked on top of each other on a Bridechamber 3-Jack bracket.
Here’s a picture of the top board, which has the power input connector. The big 4.7 uF yellow box capacitor (Mouser part # 1430-1475) fits on the upper right corner. It is secured to the board with a Scotch double-sided foam square. The jumpers that would have been underneath the capacitor were omitted and wires were soldered onto the capacitor lead. All parts were placed according to the Tellun instruction manual for assembly with the MUUB-4. One tricky bit was that the schematic diagram is generic and it happens that U1 and U2 are reversed from the MUUB numbering. The pinout of one of the op amps is also different from the schematic. I wrote in the MUUB numbers on the schematic and corrected the pinouts as well, as an aid during assembly.
Below is a picture taken half way through construction. The bottom board is in place and has been wired up to the jacks and pots. Notice the two electrolytic bypass caps lying down over the power connector area. I used 2.2 uF values for these. Incoming power is supplied by jumpers (red, white, and black) to the top board. The MUUB board has convenient locations to connect power jumpers. Note also that only the top board needs ferrite beads (Mouser part # 81-BL01RN1A1F1J are used here).
Below is a picture of the completed module, as seen from the side. I chose Alpha carbon pots, partly for cost and partly because of readily available 1M log pots (Mouser part # 313-1500F-1M). I bought 10 of these pots and matched them for value, as suggested in the Tellun manual. I trimmed off the end of the Bridechamber bracket, which is very long. The bracket has mounting holes that match the MUUB board. Nice!
Here is a closeup of the sandwiched PC boards. The capacitors fit snugly and actually contribute to the stability of the assembly. You can see here the small cutout on the Bridechamber 3-jack bracket that’s needed to accommodate the nearest pot.
