PL 700 B

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#21
Progress

Yup, pic o' the top of the transformer ought to do it.
I made some progress today after Joe got back to me and answered a couple quick questions. Here's what I've gotten through, so far. I used the old hold-downs, so I didn't have to drill any new holes in the chassis (see picture), since it's been painted for a while now. When I got the amp, it was in pretty bad shape, so I had to take it all the way down to the bones and start over — with some customizing. Also, there's a picture of the matched set of transistors I bought from Ed, another really generous member of the PL community. Does everything look okay? Also, probably a stupid question, but I'm about to solder the wires onto my backplane. Should they be soldered from the back or from the front, component side?

WOAPL Buildout — 54.jpg WOAPL Buildout — 55.jpg WOAPL Buildout — 56.jpg WOAPL Buildout — 57.jpg WOAPL Buildout — 59.jpg
 
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#22

NavLinear

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#23
Your chassis looks good - I like the grey and red combo.

I would suggest that you get a new bridge rectifier and install snubber caps across all four diodes. The cost is minimal and installing a new one will increase reliability. The snubber caps filter out the diode switching noise. You will need to get modern output transistors as you're adding the White Oak backplane boards. Are you planning on a quasi or fully complimentary output?

Solder wires from the top - see Joe's assembly notes for the backplane.

Have fun with this.
 
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#24
Your chassis looks good - I like the grey and red combo.

I would suggest that you get a new bridge rectifier and install snubber caps across all four diodes. The cost is minimal and installing a new one will increase reliability. The snubber caps filter out the diode switching noise. You will need to get modern output transistors as you're adding the White Oak backplane boards. Are you planning on a quasi or fully complimentary output?

Solder wires from the top - see Joe's assembly notes for the backplane.

Have fun with this.
Thanks for the input. I'm going to take your advice. But I guess I'm confused as to the transistors. However, I remember that there's something about which ones Joe recommends in the backplane literature. I'll go over it again.
 
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#25
Your chassis looks good - I like the grey and red combo.

I would suggest that you get a new bridge rectifier and install snubber caps across all four diodes. The cost is minimal and installing a new one will increase reliability. The snubber caps filter out the diode switching noise. You will need to get modern output transistors as you're adding the White Oak backplane boards. Are you planning on a quasi or fully complimentary output?

Solder wires from the top - see Joe's assembly notes for the backplane.

Have fun with this.
Do you have the specs or numbers on the bridge rectifier and snubbers? Sorry, I'm new to this, so I may ask stupid questions from time to time, or, every time. And I'm going quasi, mostly because I'm unfamiliar with the comp. configuration. Also, I'm committed now. The backplane kit I bought is only for quasi, as far as I understand.

As relates to my admitted ignorance and lack of experience in this field, until the last year or so, the below photographs from my little shop on the water represent the sort of projects I was inclined toward for the last 45 years. But I learn fast.

WOAPL Buildout — 7.jpg WOAPL Buildout — 33.jpg
 

laatsch55

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#29
No problem, you didn't know we HAD A parts database complete with Mouser part numbers.....
 

WOPL Sniffer

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#30
Do you have the specs or numbers on the bridge rectifier and snubbers? Sorry, I'm new to this, so I may ask stupid questions from time to time, or, every time. And I'm going quasi, mostly because I'm unfamiliar with the comp. configuration. Also, I'm committed now. The backplane kit I bought is only for quasi, as far as I understand.

As relates to my admitted ignorance and lack of experience in this field, until the last year or so, the below photographs from my little shop on the water represent the sort of projects I was inclined toward for the last 45 years. But I learn fast.

View attachment 26843 View attachment 26844
I think the backplanes come with both parts. When I build, I omit the quasi stuff.
 

Gepetto

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#31
I think the backplanes come with both parts. When I build, I omit the quasi stuff.
Hi guys

Backplanes are ONLY full comp anymore.

I dropped the quasi comp option for the PL400 at RevB. RevC is full comp only.

The PL700 has only been full comp in both RevA and RevB configurations.

Reason: Customer input. The only quasi comp backplane version ever built is the one I have in my lab for test purposes. All upgraders only wanted full comp and built them that way. The RevC PL400 backplanes are easier to build as a result because it eliminates option jumpers.
 

WOPL Sniffer

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#32
Hi guys

Backplanes are ONLY full comp anymore.

I dropped the quasi comp option for the PL400 at RevB. RevC is full comp only.

The PL700 has only been full comp in both RevA and RevB configurations.

Reason: Customer input. The only quasi comp backplane version ever built is the one I have in my lab for test purposes. All upgraders only wanted full comp and built them that way. The RevC PL400 backplanes are easier to build as a result because it eliminates option jumpers.
Joe, why the quasi parts in the kit? I usually have several parts left which the package says quasi only (700 backplanes)? Thanks
 

Gepetto

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#33
Joe, why the quasi parts in the kit? I usually have several parts left which the package says quasi only (700 backplanes)? Thanks
That is for the PL14_20E control board Perry. The PL700 backplane parts bags do not have any reference to quasi.
 

WOPL Sniffer

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#34
That is for the PL14_20E control board Perry. The PL700 backplane parts bags do not have any reference to quasi.
DUH, yer right, After building backplanes and control boards all week, I knew that... Guess I Need a break. Pretend I never asked.. :)
 
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