#1651

[@davidv1289]

The PCB have to be put in with the non-notched edge first followed by the notched edge. With the boards held vertically, component side out, the notches fit into the pins in either side of the chassis. This allows the unit to be operated with all three boards connected and gives access to all components for troubleshooting. That is why the ribbon cables are so long and also explains the odd power connection for the upper board. An interesting design that reduces form factor while retaining maintainability. Regards, David

[@georgesampson4714]

The voice says "Hmmm, what do I do?" The tone of voice says "I don't want to mess with these." The conscience says "Man, I hate to throw away electronic stuff especially if it is HP." The procrastinator says "Oh just shove them back under the bench for a later day." What will he do? What will he do???

[@IMSAIGuy]

that about sums it up

[@absurdengineering]

There’s one thing that bugs me: why don’t repair techs have a ready to use stash of zip-locking baggies? Sure, no time wasted bolting it back together - I understand that, but at least put the loose bits into a baggie and tape it inside somewhere? Takes no time but leaves a bit less sour taste for the next person to work on it. OK, I’ll get down from my fence now 😂

[@SpinStar1956]

What I do is make one or two work if possible and then scrap the PCB's out for future donor-duty. I then take and gut them out leaving the power supplies as that gives an excellent boilerplate-start for a custom project!

[@joepiscapo936]

how many version of the top board are there ... my top board looks different? Different year ? Don't have those 5 ic on the left? Actually mine looks like 10:50....maybe newer one? 88?

[@chongli297]

What do people use fast pulse generators for anyway? The only application I know of is to measure the rise time on an oscilloscope. But you don't need 50MHz for that, you just need a very fast edge.

[@JD-eq1gk]

Pulse RF testing.

[@jacksong6226]

Calibrating radiation survey meters

[@mr1enrollment]

you sound defeated to begin with,... buck up Charlie Brown, this can make many videos!

[@nexus1972]

No clue why you even bothered making this. These are nice signal generators if you dont have dead hybrids. I hope you arent this rough with all equipment. The boards fit into the standoffs each side so for calibration time you can have access with all boards connected and out of the way. Top board is the microprocessoiir board - get the manual and follow the procedures. Do the psu calibration first. Top board is just the processor board controlling interface and is soldered on the board but where it meets the main board there is a connector. These are about as easy to work on (hybrid issues aside) as any equipment ive ever worked on.

[@simontay4851]

Wow, thats complicated. Where to even start. Hope you can find the service manual.

[@nickcaruso]

Reuse the chassis for new projects?

[@markgreco1962]

20$ my bet at least one will come to life.

[@IMSAIGuy]

when we get the part 4, remember you can always become a Patron

[@IMSAIGuy]

Do I have a new Patron?

[@markgreco1962]

@@IMSAIGuy hurts to loose… your HP repair tear down videos are my favorite part of the channel, you rarely fail. you betcha! As weird as it sounds that’s what I’m asking Santa for. Worth the 60.00

[@EfieldHfield_377]

Hmmmm, not much utility you can get out of thing and they looking like way more trouble than its worth. I would recycle what I can toss the rest.

[@IMSAIGuy]

foreshadowing

[@absurdengineering]

@IMSAIGuy I promise I’ll repair at least two of them to working order on video if you feel like getting rid of them. Just let me know how much the shipping will be to east coast.

[@EfieldHfield_377]

@@IMSAIGuy LOL, well said and perhaps a likely outcome. We shall see how much self punishment you enjoy on this one.

[@EfieldHfield_377]

@@absurdengineering There is a sceen from Jurasic park movie I sort of remember that reminds me of this. After everything has gone wrong the math guy comments on the scientist something to the effect, they were so caught up in "could I" as opposed to "should I". There are limited use cases for this piece of equipment, certainly anything I could think to do with it I could do with an arb, but I also understand where is the fun and glory in that. To repair it, then place it on my bench eating up far more space then it is worth to just about never be used. I have this bluetooth amplifier sitting in my garage that my girls broke than I promise to fix some day to use. Can't seem to get rid of the thing, yet I can't seem to find the time to fix it. Thing is I almost never listen to music so I keep asking myself why is it still there. I'll take the blower to it next weekend - at least need to get the dust and leaves off the thing.

[@absurdengineering]

@@EfieldHfield_377 I mostly work on this stuff to learn how to design things :) Will gladly give 2 out of 3 of them away for shipping after I’m done. I’ve learned from HP service manuals how to work with current-mode circuits using bipolar transistors - not that I have any use for it most of the time, but I like learning!