PL 3300 Series II rebuild/upgrade

Got my Care Package from Dennis and spent the day building the two upgrade boards. They may be a little crude, but they'll be functional (fingers crossed). I'll need to cut them down a bit, so they'll fit nicely in the chassis. I'll also build stand-offs for mounting. But I checked all the connections to make sure everything is arranged as designed, and they appear to be ready for installation. The phono-stage is pretty straight-forward, but I'll re-check all the pin-out connections on the power supply before I install it. Gonna go de-solder later today and then get the board nice and clean.


Power Supply
3300 — 6.jpg 3300 — 1.jpg

Phono-Stage
3300 — 5.jpg 3300 — 2.jpg
 
Gepetto said:
The existing bulk caps are still used in conjunction with this add on circuit. Thus there is very much more capacitance on both input and output after this add on is installed.
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My question is this: IF you use the LM7815 and the LM7915 regulators, the data sheet says Min input voltage is +17.5 volts and -17.5 volts respectively, is the voltage from the power supply that AFU? I don't have a skizmo in front of me so I don't know where this upgrade is tied in on the circuit so help me out here. As a matter of fact, I don't see a skizmo even available for the 3300... :(
 
I see there are a couple pages missing from the upgrade or I probably could have figured it out but it doesn't show what color wires he used on his upgrade board. I see what color and where they go but not what/where he used them on the add on board. did I miss a page? I see a few missing...

HUH??
 
This is what I was able to find from my Lou files. I hope this helps make sense of the upgrade Lou designed. I didn't have the PCB this time, so I just used some project board and soldered the connections directly. It probably wasn't necessary, but if you look at the photo of the top of the board, you can see that I included a jumper, the red wire, for the negative trace.

View attachment Lou's Rules.pdf
 
Unfortunately, I can't find the parts list from Lou's upgrade. But the suggestions elsewhere on this site are what I purchased from Dennis for this project. I have another 3300 with Lou's upgrades in it, and it performs beautifully. It's paired with a 400 Series II I upgraded a couple years ago, also with a kit Lou sold before he passed away (we were buddies and lived near each other in the Bay Area). I'm doing this 3300 for the WOPL early 400 I'm still working on. This 3300 will take the place on an NAD unit that recently went to meet its maker. The thing developed a bad buzzing and suffered an audible deterioration in performance. I may go through it at a later time, but I was just using it until I found another 3300 to put in its place. I think I have the printed material for Lou's 400 Series II upgrade around somewhere as well. But I haven't a doubt that the WO kit is far superior anyway. But if I run across it, I'll post it, just for sake of reference and discussion.
 
No, I understood most everything, I just didn't see the page with the wire colors. I see now, thanks. I may have to try this.... Sux though that I see no skizmo for the 3300. I looked but not too hard, it's not on HiFiEngine.... No luck.
 
Without the schematic, I still don't see how the LM7815, and the LM7915 *which have a minimum + 17.5V and -17.5V inputs. If the original board has 20 volts coming out of the power supply to the rest of the board, then I can see these working.
 
I'm not sure what the policy is on this site, but this is a copy of 'my' original 3300 Service Manual, with schemazmataz. The scan isn't great, but it's the best I can do for the moment. Because I've always had this (from my original 3300 purchase in 1980), I've never tried to find other copies. But my guess would be that Ebay would be the likely source, but at a price.

As for the efficacy of the upgrade, you'd have to ask Joe or Dennis. Joe looked it over and pronounced it a wise upgrade. But I can't specifically answer your question on the voltage.

View attachment 3300ServiceManual.pdf
 
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You guys are all, most likely, much more experienced and advanced than myself in electronics bench-work. So this may be silly and pointless, but today I de-soldered the components to be replaced on the 3300 board. For the first time, I used my soldering/de-soldering station I've been repairing for a while now. I told a friend of mine, who is an E.E. at Apple, that I wanted to buy a de-solder unit. He said he had one I could have. It had been dropped and had since had problems, but it was mine if I wanted to try and get it working again. It didn't have any cords or irons, but I got those cheap on Ebay. Anyway, I took the unit apart and found a cracked fuse holder, one of three, and a couple compromised connections and a problematic bend in the chassis that screwed up the vacuum pump. Anyway, today I finally got it working and had a chance to use it. Wow! It made de-soldering SO easy and clean. I've always only used suckers and wick for the job. Today, no damaged pads. No damaged traces. No mess. I didn't even need to go back in and use wick to remove the excess solder. The vacuum removed it all. Most of the components practically fell out by themselves. I only have $55 in this thing, and I don't know what comparable units cost, but I feel like it would be worth it for anyone doing any amount of this kind of work. Just thought I'd share.

View attachment 31760 View attachment 31761
 
WOPL Sniffer said:
Without the schematic, I still don't see how the LM7815, and the LM7915 *which have a minimum + 17.5V and -17.5V inputs. If the original board has 20 volts coming out of the power supply to the rest of the board, then I can see these working.
Click to expand...

The power supply output is approximately +/- 19V dc - measured.
 
scottonnob said:
You guys are all, most likely, much more experienced and advanced than myself in electronics bench-work. So this may be silly and pointless, but today I de-soldered the components to be replaced on the 3300 board. For the first time, I used my soldering/de-soldering station I've been repairing for a while now. I told a friend of mine, who is an E.E. at Apple, that I wanted to buy a de-solder unit. He said he had one I could have. It had been dropped and had since had problems, but it was mine if I wanted to try and get it working again. It didn't have any cords or irons, but I got those cheap on Ebay. Anyway, I took the unit apart and found a cracked fuse holder, one of three, and a couple compromised connections and a problematic bend in the chassis that screwed up the vacuum pump. Anyway, today I finally got it working and had a chance to use it. Wow! It made de-soldering SO easy and clean. I've always only used suckers and wick for the job. Today, no damaged pads. No damaged traces. No mess. I didn't even need to go back in and use wick to remove the excess solder. The vacuum removed it all. Most of the components practically fell out by themselves. I only have $55 in this thing, and I don't know what comparable units cost, but I feel like it would be worth it for anyone doing any amount of this kind of work. Just thought I'd share.

View attachment 31760 View attachment 31761
Click to expand...

It's good to have something that sucks well. No mess.

$55 is a good deal - nice job.
 
scottonnob said:
I'm not sure what the policy is on this site, but this is a copy of 'my' original 3300 Service Manual, with schemazmataz. The scan isn't great, but it's the best I can do for the moment. Because I've always had this (from my original 3300 purchase in 1980), I've never tried to find other copies. But my guess would be that Ebay would be the likely source, but at a price.

As for the efficacy of the upgrade, you'd have to ask Joe or Dennis. Joe looked it over and pronounced it a wise upgrade. But I can't specifically answer your question on the voltage.

View attachment 31759
Click to expand...


Actually, that is an awesome copy compared to some we have to work with. Thanks
 
Joe,

Do you suggest replacing Q-1, 103, 203? If so, with what? The same, just new units? Dennis didn't have any thoughts, but suggested I ask you. He'd like to know as well.

Thanks, Scott
 
scottonnob said:
Joe,

Do you suggest replacing Q-1, 103, 203? If so, with what? The same, just new units? Dennis didn't have any thoughts, but suggested I ask you. He'd like to know as well.

Thanks, Scott
Click to expand...

Hi Scott
Those 3 devices just form a turn on/turn off muting circuit and are not really audio path devices. It will do no harm to replace them but it won't change anything sonically either.

Joe
 
scottonnob said:
A good friend of mine, who has since passed away, used to sell upgrade kits for PL products. None of his stuff is still around, but I found this document in my files. It's from his kit I used to rebuild my first 3300. So I'm just curious what you guys think of this particular modification.

View attachment 30546
Click to expand...



I was definitely interested in the + and -15 volt regulator, not just to do a 3300, but with some other projects I have going. I wanted to make this a little easier (and, I am brushing up on my CAD skills) for the fellow DIY'rs

I took it a step farther with LED monitoring of the +15 and -15 unregulated input, LED monitoring of the outputs also (makes it easier to check the circuit at a quick glance) and also put connectors on it to give it a better look. I don't like to put my work on a perf board, they look WAY to primitive and soldering leaves a terrible look....

These are pretty flexible in that we can mount 12 volt regulators on them and building with these boards, we can change out capacitors for different filtering needs (or eliminate caps if you wish) If you are interested, let me know and I'll send you one. They are nice and small and with a horizontal mounting of the regulators and heat sinks, they should fit nearly anywhere. Joe, how bad does my skizmo look???





IMG_4663.jpgPL3300 Regulator.jpg
 
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