Phase Linear 4000 Series two.

Went searching thru all my old junk to see if I had any OPT I could pop in and guess what. In the past I had been sorting the old OPT by the date code and calling them 'matched" because I knew they all came out of the same unit, they all had the same designation/type (IE 15025,15024,) number and by the date code even though I did not know it was a date code.
 
I need two op amps, the transistor set, new caps, and 2 1.8k 2 watt resistors. I think I may have all the rest. Sure I have the caps too. I am gonna hook it up in my shop probably.
 
VSAT88 said:
I am not sure what you mean. I took the old board out to re populate it. Gotta get some parts.
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Oh OK , I see that you took the 7.5K Resistors out? bottom pic and I see a blob of solder by the Cap (Top Right ) I can look later at my working board , but its full comp. the Zennor diode has been replaced & I would add sockets for the op-amp , I had a lot of problems w the Pots so I would clean them, and ohm them out.
Oh I just bought some silicone wire Wow its very Flexible I used the 20AWG but the next one is going to be 22awg https://www.amazon.com/dp/B0881HCN37?psc=1&ref=ppx_yo2ov_dt_b_product_details
 
Just de soldered on side of those two resistors to do a firm check on them. They will both be replaced. Lots of heat on those two. I already have the sockets for the op amps, just trying to decide what ones to use. I do not understand why only one op amp has a socket on this board?? I will replace all of the diodes on the board, transistors and resistors. I think I have two bias pots, brand new ones not 100% though. Gotta look. Did you use the .22awg on a PL amp ?
 
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Here the pic of the Connecters I added and is wired w 20awg but it tight (not a lot of room behind the board. I will make the Bias wires longer from the board so they can move around the board, I'm using 4-connecters all wired from the backplane and power and all are wired for the PL14_20G1 . I converted it to Full comp so the board has been modified. PL had a lot of design work and thinking about how to do it and this is REV 1 Yellow tape is holding the connectors for the PL.
 

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The Goal is to have a test fixture since I'm doing a bunch of them, I have a lot of parts so I'm going to update all the old PL boards w news parts and Resistors and them I can swap out them w the new PL14_20G1
This PL 400II has already had 2-PL14_20G1 boards in it and the Original modify PL one.
 

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MusicSteve said:
The Goal is to have a test fixture since I'm doing a bunch of them, I have a lot of parts so I'm going to update all the old PL boards w news parts and Resistors and them I can swap out them w the new PL14_20G1
This PL 400II has already had 2-PL14_20G1 boards in it and the Original modify PL one.
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Steve, your long lead length on the bias transistor connections is not your friend. Those want to be very short as they are carrying the high frequency signal.
 
Gepetto said:
Steve, your long lead length on the bias transistor connections is not your friend. Those want to be very short as they are carrying the high frequency signal.
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Joe
Good to know I did some test w shorter ones and did not see a different.
I was also thing if it was a problem adding shielded cables. what do you think?
 
Joe, I used some old Bell phone wire, single conductor on the amp I sold a PL 400 with the PL 14 board. They were not really long or anything, solid copper. Was that a no no ?
 
VSAT88 said:
Wow, that looks fascinating . Your knowledge level exceeds mine by a long shot!
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Not really,
I very impressed w you taking the wires off! (brave) I been in the Machine Building world forever and some times you have to think outside the box.
 
MusicSteve said:
Joe
Good to know I did some test w shorter ones and did not see a different.
I was also thing if it was a problem adding shielded cables. what do you think?
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keep em short and unshielded. Capacitance of shielded will upset stability
 
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