Famous for using a Beetle air-cooled cylinder head as a cooling fin for power transistors. His and Jim Williams writings should be required reading for anyone in Electronics!

The prototype looks like this: https://youtu.be/ytZfeUKNaAo

Nice story Lee, I've enjoyed reading it, thank you. -Rik

Yeah- This is all correct. It definitely has the TACO chip, and a native HP-IB port. I understand that getting reliable media for the tape drives is sort of iffy these days, and I only have (2) tapes

According to Ansgar's site the processor in the 4955A is the same hybrid that was used for the PPU in the 9845A that lacks the Advanced Math Chip in other words it is a hybrid processor with full 16

In the late 70's N S came out with a processor series designated as COPS (control oriented processor series). The company I worked for at the time had major field problems with controls using this

Do you mean the 9831? Same basic hardware, slightly different keys and ROMs to handle the Basic language. hpmuseum.net has some text saying this is possible, I do not have a 9831 so I can't vouch for

Greetings, all: I recently picked up an HP 4955A Protocol Analyzer. Although my bench is stacked with HP vintage test equipment in daily use, this is my first fun foray into the world of pre-90's HP

Yes, short time solution for quick testing of other tape functions before new LDR will come.

Using the old ldr isn't a good idea, the ldr will degrade more over time. At the best it will be a short time solution. I think the 5616 should work. -Rik

Code: GL5616D Diameter: 5mm Light resistance: - 10lx - 5÷150 kΩ - 100lx - < 2 kΩ Dark resistance: 1 MΩ Power: 100mW Maximum voltage: 150V DC Wave length: 540nm Working temperature: -30°C

I have breadboarded the design. One small 2x16 LCD, backlit, three switches: up, down, enter. Up and down scrolls through the available files. Enter selects the selected "disk" file. Thought I'd make

Hi Marius, It’s some time ago and I don’t remember which LDR I ordered. I looked at epay and found several sellers who sell 5mm LDR’s. So the best thing to do, is looking at the datasheet

Plan on installing this weekend on my 9000/380 with 9.10 (best I recall) Have not fired this up in over a year! Hope I'm successful. Plan on using this to control my (somewhat new) vast amount of test

Hmm...so it seems to be defective ? Rik can you propose some available on the market phototransistor for replacement ? The symptoms described below are also same as mine (especially rewinding case). A

would anyone happen to have a 12016A SCSI card? If so and you want to sell or trade for some other HP hardware, let me know. Thanks Jesse@...

When small square "PHOTO" pcb is disconnected from "09830-66565" (main board), values are: - 8.9K (completely dark - entire transport covered) - 0.29K (straight and intense light beam from phone

Did you disconnect the sensor from the PCB. The small pcb's are connected to the big one with pin which is detachable. The only way to get good readings is with the ldr disconnected. R-dark should be

Display board is fixed (thanks to Mr Matthieu Benoit) Regard the tape LDR sensor..... I was able to get into sensor board from

Hello Andres, you are doing absolutely fantastic job, like always! Piero