Saturday, January 24, 2009

Completed at last, the 6 channel UcD180

Finally got it done! Yeah! Tested working with all 6 channels. I did not really run it in as I do not have XLR inputs nor Speakon outputs.

It was a good learning experience for me. The main aim was not to drill too many holes onto the bottom of the chassis when mounting the UcD and SMPS modules. I guess this has been accomplished. I had 6 holes in total at the bottom. 2 for each SMPS module. A 5mm aluminium plate was used as the heatsink for the UcDs. This plate was mounted securely via the vertical slots on the bottom plate. Another aluminium plate was used as a shield between the 3 x SMPS modules and the 6 x UcD modules. This, according to the SMPS manual, would not be required as the SMPS is supposed to have low EMF/RFI radiation. Well, I did not have the luxury to read the SMPS manual prior to ordering the aluminium.

Next project would be to try out John Broskie's Janus Shunt Regulator on my preamp.

Wednesday, January 21, 2009

UCD updates

One channel of the UcD in test tonight. Took me some time to find the connectors for the input. The are supposed to be Molex KK 2.54mm or 0.1" series. I did not have enough quantity to order online from RS or Farnell, so had to search for compatible ones from Koba. Found the connectors there, but eventually, had to use them without the housing as this offered better connection. The mechanical construct of the housing did not render it to reuse that well after stripping the previous wires and replacing them with the mundorf silver/gold wires.

Then, it was the single ended RCA to XLR connections that caused me to search high and low for the reason why no sound is coming out from the speaker... I shorted pins 1 and 3 and used it as ground. Pin 2 was signal. But no effect. Actually it was because there was a internal lift up /ON pin on the UcD module that had to be grounded or connected to J2, pin 5 of the SMPS module. Need to get some more connectors to do this nicely.

Well... at least it is almost there... Before Chinese New Year.

Some pics here.

Saturday, January 3, 2009

Mighty Midget parts

Got some parts in the mail. They are GE 6T10 compactron tubes, Takman carbon and Mills wire wound resistors. Also in the picture is the Mundorf gold/silver wires. The wires are used as hookup in the multichannel UcD amp. Have to complete this before I can free up some space for either the Moskido or the Mighty Midget. I've already received the sockets for the 6T10. Got 12 of them from ebay... So if anyone needs a couple in Singapore, I am more than happy to sell some. ;)

I am more inclined to do the 6T10 at this moment. Possibly with a John Broskie Janus Shunt Regulator at the B+ as shown below.

Need to dig out some parts to see what I should use for the PSU. Cannot remember if I have the 6X5 or 6X4 rectifier tube around. If I am using a regulated B+, I may just use a CLC with the Nippon Chemi con 220uF capacitor.

Some pics here.