Gibsonian's Cherry Pl 700 Ser I, soon to be a PLWO-1000

Yeah, my heavy handed slip on the sig gen. I inputted 10.23 volts to the "in" rca jacks. I thought I was outputting a 110 volt square wave, but.....................when you think about the gain you have with 1.7 volts input, what would 10.23 volts input give you????? Yeah......scary ain't it. Blew the coil on the DC protect relay, then blew it up. The output stage was literally screaming till the fuses went. Took out D4 thru D10, 4 drivers, 2 outputs, Q8, Q9, Q5, Q7, Q10. And some caps that I haven't chased down yet. Had to give up on that board, put another one together and promptly blew the +/- 20 volt supply out of it along with Q6, at that point I pulled the board, pulled al;l outputs, pulled up the output sockets, vacuumed any thing that was between chassis and sockets and went back together with it, testing for shorts and opens after each device was mounted. Thought i had finally got the chassis debugged so I put together a third board feeling that Scott deserved a board that had not been stressed. Brought this one up on the variac and DBT and had some runaway current. Seems that the 2N3403's I had replaced after the big chassis debug did not have enough "Gain" to stabilize the bias circuit. Replaced the 2n3403's anfd that's whenb things settled down enough to actually take it off the DBT and variac. Everything dialed right in then. I have been giving "Cathy" a very stressful; shakedown hoping that if I stressed some outputs that they would show.
When you think about what the soa curve would look like with an input square wave of 10.23 volts..................
 
Gibsonians PLWO 1000 has taken the job of saving someones life today. One of those little smart ass F^%$#^ punks that's been in the oilfield a few months and then proceeds to tell ME how things ought to be ON MY LOCATION!!! F^%$ EM!@ And he was a VENDOR!! F^%$# EM!

Anyway "Cathy" has swooped in and saved his life, good Girl. She's a SWEETIE!!
 
Not all sad. Somebody in Iowa might have a bit more jump in his step, might be smiling a wee bit more, could have a few extra cold ones while enjoying Cathy's warm and satisfying company.
 
LeeL Is that your third PL 700 refit you knocked off this year? Would a Pioneer Spec 1 amplifier be a worthy project for upgrades?

Nando.
 
A Spec 1 pre-amp or the Spec 2 amp?? Why, got one?? Thgey can be greatrly improved with various stuff as most are getting pretty long in the tooth. They have some relays that over time have become troublesome, and some upgrades to the drivers and meter amp boards are pretty standard. They nalso have some vtemp compensating diodes that if mishandled can cause some long waiting periods to find em. EW and Markthefixer at AK are trying some workarounds for those particular parts and knowing those 2 they'll get it eventually.

4-700's and 4 - 400's now.
 
laatsch55 said:
A Spec 1 pre-amp or the Spec 2 amp?? Why, got one?? Thgey can be greatrly improved with various stuff as most are getting pretty long in the tooth. They have some relays that over time have become troublesome, and some upgrades to the drivers and meter amp boards are pretty standard. They nalso have some vtemp compensating diodes that if mishandled can cause some long waiting periods to find em. EW and Markthefixer at AK are trying some workarounds for those particular parts and knowing those 2 they'll get it eventually.

4-700's and 4 - 400's now.
Click to expand...
Sorry, I meant Spec 2 power amplifier. I think my Pioneer SA-9500 II integrated amplifier has many of the features, and similar build to the Spec 1 preamplifier. I haven't found a Pioneer Spec 2, yet, but I just have a feeling this coming year that may change.

That's plenty of Phase Linear 400 and 700 builds under your belt, Lee.

Nando.
 
Yep, you'd think they'd get easier as ya go along, but I keep finding ways to make it challenging.
 
Ok, so it didn't get boxed Friday. Still had some clean up and Jani had to do her thin g. Looks pretty darn good.
 

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It's therte.
Date/TimeActivityLocationDetailsDec 24, 2011 9:06 AMDeliveredKeokuk, IADec 24, 2011 6:06 AMOn FedEx vehicle for deliveryQUINCY, ILDec 24, 2011 3:25 AMAt local FedEx facilityQUINCY, ILDec 24, 2011 12:47 AMIn transitSAINT LOUIS, MODec 23, 2011 9:21 PMDeparted FedEx locationCHAMPAIGN, ILDec 23, 2011 3:52 PMArrived at FedEx locationCHAMPAIGN, ILDec 23, 2011 4:42 AMDeparted FedEx locationSAINT PAUL, MNDec 22, 2011 3:19 PMArrived at FedEx locationSAINT PAUL, MNDec 21, 2011 9:57 PMDeparted FedEx locationBILLINGS, MTDec 21, 2011 7:09 AMArrived at FedEx locationBILLINGS, MTDec 21, 2011 4:29 AMIn transitSHERIDAN, WYDec 21, 2011 2:36 AMLeft FedEx origin facilityGILLETTE, WYDec 20, 2011 5:16 PMArrived at FedEx locationGILLETTE, WYDec 20, 2011 4:10 PMPicked upGILLETTE, WYDec 20, 2011 9:46 AMIn FedEx possessionGILLETTE, WYTendered at FedEx locationDec 19, 2011 11:45 PMShipment information sent to FedEx
 
Very anxious to hear what Scott thinks. Kinda curious whether it made it OK also.
 
It arrived in fine shape. I've not had a chance to really listen so cannot comment too much on sound. Just too much going on here at the moment. Hope everyone had a fine Christmas day.
 
DC protect board update

Just wanted to update the group on the latest happenings with Cathy. In another thread I crapped on it kinda by going into the problem with Cathy cutting out (no output) at high volume play. Lee sent me a new dc protect board and I installed her and the issue appears to be gone. I need to test a little more but am 99% sure it's fixed. Had the needles pegged last night and no drop outs. Issue seems to be contained within the original dc protect board. To be 100% sure I will need to test again recreating original conditons - drink a few extra cold ones and have a loud music enthusiast freind drop over for a listen.
 
Rule number one, hardware fails :-) Glad you pinpointed it to a defective part and got it solved.
 
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