Hitachi v-1100 oscilloscope repair parts or advice

[Richard King]

Recently purchased a nice looking Hitachi V-1100 100Mhz, 4CH, oscilloscope. It has a broken component inside and I am having difficulty locating replacement parts or repair info for the device. I found a service manual for the scope but it seems to be a specially built hybrid circuit mounted on a thin plate of ceramic. Both ch1 and ch2 have the same plate but ch1 is broken into a few pieces. I de-soldered it and tried to piece it back together with some wire scraping and sloppy soldering but to no avail. This is a nice looking scope and would love to get it going. I have no knowledge of oscilloscopes or how they operate aside from some very limited uses. It seems the part is from the Ch1/Ch2 pre-amp circuit but when I examine the schematic it simply shows a block diagram of this IC10 component. The Hitachi part number is IC10/UH-100/8410385. The parts description says its a hybrid ic unit. Keep in mind I'm just a dumb auto mechanic but got an inquisitive side to me that allows me to fix (and break) lots of things. I also explored the idea of integrating a similar component from ...say a tektronics scope but.....only hitachi is like hitachi. Anywhere I can possibly purchase components??? Nothing on Ebay and nothing in a general search so I'm out of luck at this point with a junk machine taking up space in my shop. If you look at the last photo, next to my finger, you can see the white ceramic plate broken and about 2" away is Ch2 ceramic plate in good shape. If I cannot find any parts or anyone to assist with fabrication information then ill remove Ch2 and install in Ch1 and leave Ch2 dead. At this point I'm considering the unit junk.
Thanks for your time!!!!
Richard
Butte, Montana, USA

 

[Harald Kapp]

Anywhere I can possibly purchase components???

Most unlikely. Hybrid circuits like this are usually custom specificic made. In that case only the manufacturer has access to them. You'd have to find another scope of the same type to scavenge a working module.

 

[Richard King]

any ideas what the components on the ceramic wafer are?? I posted pics .....had to attach the broken ceramic plate to duct tape to hold it together and that's the tape overhang under the wires that I didn't trim off.... I also figured I could scratch the protective coating on the conductor wires(green coating) and solder jumper wires across the broken parts of the ceramic and re-complete the circuit but haven't dug into it just yet. ADVICE????

 

[Harald Kapp]

There are tantalum capacitors, ceramic capacitors, transistors or diodes.
Most importantly there are printed resistors - those dark grey rectangles. For of them are broken and next to impossible to repair. Note that these resistors are trimmed as you can see from the little cuts made into the grey area. The resistors are manufactured to a bit less resistance than required, then (laser) trimmed by cutting into the resistive area to increase the resistance to the final value. If you wanted to repair these resistors (assuming you were able to do so) you'd need to know the trimmed value or another parameter which could be measured and used to trim the resistors.

 

[Richard King]

well....my idea is to measure as much of the resistance I can....and solder another resistor into the board effectively leaving it broken but jumping the broken plates and reconnecting the circuit....(there are no parts available for this machine....in fact..this is the only machine I can find on the internet..the one I purchased.....theres a v-1100a but its not the same....mines electronically adjusted and the v-1100a is mechanically...pushbuttons)....bypassing the resistive pad.......dead accuracy for this machine is not necessary....in fact ill realistically not need to measure anything over 10Mhz and if the signal is kinda distorted....I can prob live with that for my uses.....

 

[Richard King]

Also, the components labelled 10 16v have one wide plate on the side of the 16v and 2 small plates on the other side. So this is a 3 wire(plate) unit...... almost looks like a diode bank to me with 1 common lead but I haven't tested for continuity. Any ideas on the metal bar/rod on the circuit??? Ive never seen these components before. The others I can clearly see are transistors and the 2 small units on the far left side of the board....yellowish colored and grey ....are they resistors or capacitors??

 

[Harald Kapp]

the components labelled 10 16v have one wide plate on the side of the 16v and 2 small plates on the other side. So this is a 3 wire(plate) unit

No, these are tantalum capacitors, 10 µF, 16 V. The 2 small plates are electrically a single contact (anode).

 

[Harald Kapp]

the 2 small units on the far left side of the board....yellowish colored and grey ....are they resistors or capacitors??

Capacitors. The resistors are printed, apart from the one wired resistor which looks like a later patch.

 

[Richard King]

Well Sir, I shall do what I can....thanks for your insight!!!! Ill post the Frankenstein circuit board when its done. Again, thanks to Mr. Harold Kapp for your time, patience, and wisdom!!!!!

 

[kellys_eye]

I also figured I could scratch the protective coating on the conductor wires(green coating) and solder jumper wires across the broken parts of the ceramic and re-complete the circuit

Personally I'd give it a shot.

Cut and glue a thin plate to fix the broken parts to.

You could get ballpark component (resistor) values from the other module to make the initial selection (get 0.1% resistor to fit) but you'd have to accept that channel as being out of calibration (you could draft a chart to plot the actual error if you thought having greater accuracy was a requirement) but using it for approximation measurements i.e. waveform there or not, correct shape or not etc would be better then nothing.

 

[Richard King]

I was looking around my work area and saw gorilla tape and i know that stuff is good so i used that as the ceramic plate adhesive. Seems to work and gives me a little flexibility.... Still havent begun repairs...

 

[Harald Kapp]

I'm curious...

 

[elebish]

Recently purchased a nice looking Hitachi V-1100 100Mhz, 4CH, oscilloscope. It has a broken component inside and I am having difficulty locating replacement parts or repair info for the device. I found a service manual for the scope but it seems to be a specially built hybrid circuit mounted on a thin plate of ceramic. Both ch1 and ch2 have the same plate but ch1 is broken into a few pieces. I de-soldered it and tried to piece it back together with some wire scraping and sloppy soldering but to no avail. This is a nice looking scope and would love to get it going. I have no knowledge of oscilloscopes or how they operate aside from some very limited uses. It seems the part is from the Ch1/Ch2 pre-amp circuit but when I examine the schematic it simply shows a block diagram of this IC10 component. The Hitachi part number is IC10/UH-100/8410385. The parts description says its a hybrid ic unit. Keep in mind I'm just a dumb auto mechanic but got an inquisitive side to me that allows me to fix (and break) lots of things. I also explored the idea of integrating a similar component from ...say a tektronics scope but.....only hitachi is like hitachi. Anywhere I can possibly purchase components??? Nothing on Ebay and nothing in a general search so I'm out of luck at this point with a junk machine taking up space in my shop. If you look at the last photo, next to my finger, you can see the white ceramic plate broken and about 2" away is Ch2 ceramic plate in good shape. If I cannot find any parts or anyone to assist with fabrication information then ill remove Ch2 and install in Ch1 and leave Ch2 dead. At this point I'm considering the unit junk.
Thanks for your time!!!!
Richard
Butte, Montana, USA

This component is called a hybrid because it contains several different components formulated to create a circuit designed as a space saver and maybe for good accuracy since it is laser trimmed. Removing the "good" hybrid component and making measurements will be difficult without a "laboratory" grade meter. That process will be made more difficult because those components are probably connected in series, parallel or both making readings not reflective of the individual values. Even if the hybrid was put back together, making the proper connections to connect the broken ceramic halves together may be impossible. Maybe a schematic of the hybrid can be found whereby you may be able to make your own component.

 

[Richard King]

Scope seems to work....and fairly accurately when compared to other scopes on the same circuit.....every once in a while it becomes fidgety and just wont work right but for the most part.....i got lucky. heres a before and after repair pic......proving if you think you can, or think you can't.....your'e right!!

 

[Richard King]

ok....wont let me upload any files....oh well.....thanks to all that helped