400 S2 - Wopl In Progress

[74sdta]

Slow progress this week due to work stuff. Backplanes ready for wiring and some chassis work. Hope to start control board tomorrow.

 

[George S.]

Slow careful progress is good. You spent a lot of effort cleaning the boards and it shows.
And a new chassis. Top shelf.

 

[Hexis22]

Slow progress this week due to work stuff. Backplanes ready for wiring and some chassis work. Hope to start control board tomorrow.

View attachment 79830 View attachment 79829 View attachment 79828

Be very careful placing the P-clamp on Q6 after you soldered the transistor into the PCB.

 

[mlucitt]

Be very careful placing the P-clamp on Q6 after you soldered the transistor into the PCB.

And I thought I was doing it correctly by inserting the 2N5088 Transistor in the empty P-clamp and placing a drop of Superglue Gel on top of the transistor, then soldering the assembled Bias Transistor/P-clamp onto the Backplane Boards after the Superglue dries!

I even sand off the 2N3403 stamp on the P-clamp so there is no confusion in the future.

 

[Hexis22]

And I thought I was doing it correctly by inserting the 2N5088 Transistor in the empty P-clamp and placing a drop of Superglue Gel on top of the transistor, then soldering the assembled Bias Transistor/P-clamp onto the Backplane Boards after the Superglue dries!

I even sand off the 2N3403 stamp on the P-clamp so there is no confusion in the future.

I agree, my comment was referring to his backplane picture shows the bias transistor already soldered to the board without first installing the P-clamp...

 

[74sdta]

P-clamp was used during soldering of the transistor. Shortly after that pic, it was slid back on and the old hardware was used to secure it until ready for the chassis.

Super glue is a good option.

 

[74sdta]

Quick update - Backplanes are done and sitting in the chassis for wire routing. Started work on Control Board.

Question - The 22Ohm resistor for R37L/R and R41L/R is labelled as red-red-black-gold. The resistors in my kit are red-red-brown-gold (22.1Ohm). Is this correct?

 

[Gepetto]

Quick update - Backplanes are done and sitting in the chassis for wire routing. Started work on Control Board.

Question - The 22Ohm resistor for R37L/R and R41L/R is labelled as red-red-black-gold. The resistors in my kit are red-red-brown-gold (22.1Ohm). Is this correct?

Correct, either 22 or 22.1 ohms are used. This is a non critical resistor value.

 

[74sdta]

Thanks Joe!

 

[MarkWComer]

Correct, either 22 or 22.1 ohms are used. This is a non critical resistor value.

Consider how many brown carbon resistors we used in the past that were 20% tolerance!

 

[Gepetto]

Consider how many brown carbon resistors we used in the past that were 20% tolerance!

Yup, sums it up Mark...

 

[74sdta]

Good evening PAC!

Finished control board last weekend and working on wiring as time allows. Hope to start the bring-up coarse tomorrow.


Can't wait to get this wrapped up.

 

[Hexis22]

Nice work.

 

[74sdta]

Nice work.

Thank you sir! I have used your awesome builds as a reference.

 

[74sdta]

Good evening! I am writing this and listening to the newest WOPL 400. OMG!!!!! Finished wiring this morning and tested this afternoon - All good. Pulled the stock 400 out and put the WOPL in for break-in. I still need to calibrate the meters but it has been a long weekend. Some parting shots;

 

[laatsch55]

Good evening! I am writing this and listening to the newest WOPL 400. OMG!!!!! Finished wiring this morning and tested this afternoon - All good. Pulled the stock 400 out and put the WOPL in for break-in. I still need to calibrate the meters but it has been a long weekend. Some parting shots;
View attachment 80361 View attachment 80364 View attachment 80363 View attachment 80362

NICE!!!!

 

[Hexis22]

Good evening! I am writing this and listening to the newest WOPL 400. OMG!!!!! Finished wiring this morning and tested this afternoon - All good. Pulled the stock 400 out and put the WOPL in for break-in. I still need to calibrate the meters but it has been a long weekend. Some parting shots;
View attachment 80361 View attachment 80364 View attachment 80363 View attachment 80362

Congrats!

It’s a great feeling to listen to something you assembled.

 

[74sdta]

Appreciate it!

Got the meters calibrated just now and putting the top on. B+/- = 85V, DC Offset = .2mV (L)/.7mV (R)

Off to find some handles for this one. Will likely pull the face plate back off and clean-up the holes drilled for rack mount.