really messed up HP3310B repair probability? *revived*

[coppercone2]

I am impressed how good this unit is though, because despite the power system getting hit by the electrical equivalent of a freight train, it still produces waveforms that are 80% correct, modern things cry when its off by 1v

[coppercone2]

you know what really fuck these transistors with the stupid labels, I want to make a decade switch that switches in random transistors so I can rapidly test a bunch of them. this is bull shit

every part on this thing is a fucking mystery, half of them are not on lists.

I also have a blue wire that is missing for some reason and a bare wire comming out of one of the switches, I think some how a whole bunch of insulation just yanked off a wire 

I thought it was a shield ground but its a long bare wire coming out of the switch and it looks like when I took pictures before taking it apart one of the pictures has a missing blue wire.......... it must have fell off some how

I hope this replacement PCB works LOL, I am about to break fair market value with this unit ! pray for utility from this instrument

lets get bishops legs back, at least its talking

[coppercone2]

right on, the 3310b is reading voltage rails properly when the new board is installed, all 4 of them.

There must have been a grievous fault to disrupt everything on the other PCB. The only problem is now I need to fix a few ripped wires

I hope the oscillator works with the new board but i don't feel like working on it anymore right now, finished the harrison nicely..

I need to fix a little bend in the chassis and maybe clean out the potentiometers and relubricate them

[coppercone2]

I am not working on this until I fix my Fenix flashlight and traveling wave tube amplifier control board, its seriously aggravating me and causing second guesses and im working too ghetto /lazy . i think i have been repairing too many things (#6 or 7 now)

i just know if i keep workin on it without cleaning and relaxing ima fuck something up, there is something going on with the chassis again because when i compress it the waveform goes from non existent to half shitty but different then with the other board, I think I will get some star washers, one of those beveling kits from harbor freight that you can bang on washers to make them into bowls and wait for the crimp tool, redo the wires with silicone and new crimps and keep workin on the chassis till it fits together almost flush witout tension and im missing like half the screws and doing improv and its just gotta stop and the operation needs to be cleaned up

its a bigger job then i thought but i gotta calm down i have been hitting home runs non stop with the repairs up to this guy, i should count my lucky stars that everything has been going as smooth as it has to this point, don't wanna fuck things up with a exploding sorensen and flinging this into  the wall LOL

[SilverSolder]

Top marks for stubbornness for even attempting to repair a train wreck like this! 

[coppercone2]

yeah so long I take it easy maybe I can get it to work the problem is usually I work too hard and i dont realize it then bad things start to happen and it usually takes longer then i think to reset the mind (how quickly it becomes aggravating again after a break). I gotta do this one by the book and slowly

probobly gonna do osme work on it next week like stitch together a circuit diagram on one page

[coppercone2]

Ok, So i replaced the board and redid the wires and decided not to take a break after eating dinner and i got the fucking thing working

the 10v rail is bang on the 25 one is 25.3  but it works

I need to make it nicer and add some washers and shit and redo some stuff but basically it works so long I don't zap it or snap something taking it apart again

now it just needs some knobs, i think alot broke

The problem was with replacing the PCB, and some weird mechanical shit

so HP is the fucking king, despite the evil construction it works with only 1 board replacement.


But I did notice this, those 2 big diodes, when they are grounded to the chassis, it kills the voltage rails, but when their floating, its fine. Do they need to be isolated with some kinda plastic screw or something? Totally don't know whats going on here.

*nmv twisting the transistor in was making the leg short something under the chassis*


OK So in conclusion that brings this 5 year old problem to an abrupt end.

[coppercone2]

does anyone know where I can get those things that attach to the sheet metal to make a screw go into it to hold the panel down? I am missing 1 of them.

[Gyro]

I'm looking forward to seeing the finished results after all this hard work. 

The big zener diodes are only connected to the +/- 25V supply rails via 10k resistors (just to bias them) and then connected to the main signal output via small signal diodes (to clamp it against overload, but not affect the frequency response). Yes they are screwed (connected) directly to the metal bar, which is directly connected to the chassis.

As the (16V) zeners are connected to the supplies via 10k resistors, there's no way that they can pull down the supply rails, so it sounds like you've got a connection error. If you check the schematic on page 76 of the PDF manual (block A7) you can see the circuit arrangement.

I don't know if you removed the zeners from the bar, but if not then they should already be arranged for the shortest wiring being the correct polarity. If you did, then check that you have the right one in the right hole (one is anode body and the other, cathode body).

As for those sheet metal nuts, they are used for car interior trims etc. If you take one of the remaining ones to a car accessory shop, garage, maybe diy store, they should be able to find you one.


EDIT: Added a photo of the Zener connections on my HP3310A.

[coppercone2]

the zeners are fine, I did not remove them, the problem was that when I screwed them in, one of them twisted slightly to touch the chassis, they did this weird shit on my zeners where its 2 wires with 2 pieces of heat shrink that open up, imagine a knight plate mail armor without elbow protectors (dunno why), so the corner joint is exposed and it touched the chassis, sinking the supply down.

I need to replace 2x shielded wire (coincidentally the ones in your picture), from the VCO to the pins. I am just waiting on pins and coaxial cable so I don't hard solder them to the pin. My replacement board had solder on the High-output, so the 8.2 ohm resistor is soldered from the BNC to the board, but that is the only solder joint I made, I need to replace the terminal by desoldering one from the other PCB.

The other problem I have is that i forgot to put one of the brackets in.. so I need to take it apart again to put in the bracket that goes over the right side potentiometers/switches.. and I still need to figure out which car body panel screw holder thing is going to work for me. So I need to get coaxial cable with the correct AWG inside for my 4 indent crimp tool terminals, make those 2 wires, and take it apart again so I can add the bracket.

Also, I need to figure out how to get the neon bulb into position, because the holder broke, and I need to replace the neon, since its just a live wire dangling right now, the crappy plastic clip snapped and got lost and the neon had a leg snapped off on the tube.. thankfully I have alot of neons at least, so maybe I will put a blue one in lol.  And the 2x plastic stand offs I put into it are the wrong size, because it has the bracket that is missing I will need to trim those on my proxxon milling machine.

And I need a whole bunch of those bent conical star washers. Any idea on that, the ones that fit under the chamfeurs?


Maybe pictures in a while because I will probobly make up the stripped shielded cables and find the body panel screw holder but I don't want to take it apart AGAIN until I cool off mentally. I feel like super relaxed because I know its working save for some mechanical BS but dealing with that right now is too irritating.

I also need a new neon bulb holder for my harrison lab power supply, the one they had is 2x bifurated terminals that solder to the tube which is stuck into a whiter diffuser.

so those finished pictures are a long way off unfortunately..

So what would help is
1) neon bulb holder clip idea
2) beveled star washers
3) body panel holder ( I think I figured it out but I need to be sure so it does not turn into a frustrating ebay repurchase
4) having someone take it apart for me and install the bracket because its just too much back and forth
5) replacing the PCB pin contaminated with solder with a fresh one and making a 8.2 ohm resistor with a crimp on it going to the front panel
6) adding a bit of grease between those 4x transistors and the body frame, and greasing the zeners (I will do this at the last point because I don't want to take it apart then deal with a greasy chassis)
7) some replacement knobs
replacement feet, I think I have some feet but likely I will just bolt on 4x rubber feet with the rubber glued to a washer, maybe I will pick those up at home depot tomorrow, I need only like 50x of them because my test equipment is sliding around on the racks
9) mental cool down time, so I don't break it when I take it apart again (less rough with wires)

waiting for someone to list a brand new one on ebay for 20$ to make me feel like an idiot

But I know this is like writing a paper, you need to take a break eventually and look over your work at a later time, trying to get this 'out the door' is gonna screw it up

[coppercone2]

does anyone know what female crimp can go over the 1.3mm PCB pins on this thing?

I bought the wrong thing twice, once I thought I got it, then the 2nd time I thought it was a Dsub, but those are too small. So I got way too small (without thinking, I thought it would magically line up) and too small.

I want to avoid soldering it if possible. Preferably 4 pin indent crimp, but solder / folded crimp is acceptable.