I have the pdf's that are available for free on the web. But they're not high quality and small type gets blurred, especially in the full schematic.
So if anyone has a clean copy or an original they'd like to sell, let me know.
It seems every few years over the last decades, I open the preamp up and tinker.
(And if anyone has an actual preamp they're looking to sell, might be interested in that too. Doesn't matter if it's working
)
So if anyone has a clean copy or an original they'd like to sell, let me know.
It seems every few years over the last decades, I open the preamp up and tinker.
(And if anyone has an actual preamp they're looking to sell, might be interested in that too. Doesn't matter if it's working
)
je one i scanned and posted decades ago.
http://p10hifi.net/planet10/forum/AptHolmanPreManual.pdf
dave
http://p10hifi.net/planet10/forum/AptHolmanPreManual.pdf
dave
Thank you Dave but I can't see any more detail.
The crop is page 49 near the top.
The forum attachment reads a bit better when I download it and open it side by side with my copy opened in an old acrobat.
I think mine was hifiengine.
edit - I need to clarify what I typed.
-The version you uploaded seems the same resolution as what I had previously.
-The small sample crop I uploaded seems slightly improved when I zoom it in on the forum page than my previous version.
I assume the forum uses something that resolves slightly more detail out of the pdf by smoothing and sharpening than my old acrobat.
The crop is page 49 near the top.
The forum attachment reads a bit better when I download it and open it side by side with my copy opened in an old acrobat.
I think mine was hifiengine.
edit - I need to clarify what I typed.
-The version you uploaded seems the same resolution as what I had previously.
-The small sample crop I uploaded seems slightly improved when I zoom it in on the forum page than my previous version.
I assume the forum uses something that resolves slightly more detail out of the pdf by smoothing and sharpening than my old acrobat.
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The schematic in the service manual was always difficult to read due to the quality. I've always used the schematic which is attached to the bottom panel of my preamp. It is much easier to read letters and numbers, mine is 97% still there, I could/should photograph it for future use. The file size would be huge using a "real" digital camera, will the forum allow such a large file for posting?
If so, I'll try it tomorrow if anyone wants it.
If so, I'll try it tomorrow if anyone wants it.
I'm definitely interested. I tried that a few years ago, but my camera (a tablet) wasn't up to the task. And the schematic was less than pristine.
I'm not able to use the flat screen scanner as the preamp has stick on feet holding the corners of the schematic. I tried to take photos, the schematic is printed on gloss paper so lighting is tricky, and to get the fine detail, I have to use a Macro lens which will require three photos of the schematic in sections.
I want to do this right so it could take me some time.
I want to do this right so it could take me some time.
Wow! Where did you get this? This is by far the best one.
I've been using R83 and R183 (330ohm each, after the relay) on all schematics as a reference. All are blurry when enlarging to the point of illegibility. You have to know what they are in order to read the schematic.
This version is clear!
On an odd note, in the manual the text at the bottom is split into sections. On your schematic, it's all in 1 unbroken text block. It's almost as if the manual has been doctored!
Tom Holman...
The Apt Holman Pre-Amp is a piece of gear that I have always really appreciated / treasured. A close friend has owned one since it came to market, would always let me borrow it / use it in my system for extended periods... I came to know it well. *I also owned several Advent 300s from the day (since the 70s-early 80s) I still own them. Ah, memory lane...
I ran into Tom Holman at CES 2018?, I was shooked to see him, while working in the Canon booth, he came to my counter we talked about camera technology... I could not resist expressing rich praise and fondness of his work and influence on products (I tried not to gush... lols) I honestly felt a little slightly unprofessional ~ sort of imposing on him ~ wanting to learn from him, sort of flipping the tables of his presence in the booth space.
I told him I was trying to refurb my buddies Apt Holman Pre-amp. Asked him if he had any tips or advice on recapping / rebuilding / restoring the broken unit. His strongest mention was, to not try and replace the inter-stage buffer op-amps... that it was difficult to replace the originals... without prospects of oscillation. To be careful. *My buddy decide not to spend the money repairing the pre-amp.
Tom handed me an Apple business card, with his name on it and a really cool title... fitting for the man, the legend. He was a kind and gentle soul, a very nice man, a pleasure to interact with.
The Apt Holman Pre-Amp is a piece of gear that I have always really appreciated / treasured. A close friend has owned one since it came to market, would always let me borrow it / use it in my system for extended periods... I came to know it well. *I also owned several Advent 300s from the day (since the 70s-early 80s) I still own them. Ah, memory lane...
I ran into Tom Holman at CES 2018?, I was shooked to see him, while working in the Canon booth, he came to my counter we talked about camera technology... I could not resist expressing rich praise and fondness of his work and influence on products (I tried not to gush... lols) I honestly felt a little slightly unprofessional ~ sort of imposing on him ~ wanting to learn from him, sort of flipping the tables of his presence in the booth space.
I told him I was trying to refurb my buddies Apt Holman Pre-amp. Asked him if he had any tips or advice on recapping / rebuilding / restoring the broken unit. His strongest mention was, to not try and replace the inter-stage buffer op-amps... that it was difficult to replace the originals... without prospects of oscillation. To be careful. *My buddy decide not to spend the money repairing the pre-amp.
Tom handed me an Apple business card, with his name on it and a really cool title... fitting for the man, the legend. He was a kind and gentle soul, a very nice man, a pleasure to interact with.
He's also the "TH" in "THX", the X is experiment or crossover. At least that's what I think. It's a little unclear since George Lucas' student film THX 1138 predates Holman's involvement??
Anyway if true, his initials must be on thousands of movies and hundreds of thousands pieces of A/V receivers.
Anyway if true, his initials must be on thousands of movies and hundreds of thousands pieces of A/V receivers.