Racal-Dana 1999 Teardown, Repair and Calibration

I have been using this Racal counter for a long time and in the last few months it started to suffer from an intermittent fault where it would appear to freeze and stop responding. Banging the unit on the side with the palm of my hand would get it going again, and when doing this it would often restart as if its been powered on. In addition to this fault, the counter suffers from an altogether common problem with the buttons on the front which loose any tactile feel to them and become difficult to actuate - this is a common problem on these counters and thats down to the poorly designed switches Racal used for its frequency counter range.

[gerrysweeney]

Hi Jacob, I am not sure thats the right part. The one you point to is a dual-row connector, the one on the OCXO board is a single row connector. The rework of the arduino-style single header female pin header I showed in the video works really well. Gerry

[gerrysweeney]

Richard, yes you are right, for my own use thats true but its still nice to have it working well stand-alone. I am going to do an OCXO nod for it too. The cost of them second hand makes it easy to justify.

[gerrysweeney]

Thanks Dino, no problem. Glad your having ago at the Rb project, and using a PIC for LED control....great. Can I ask you to post a comment on the blog page relating to the OCXO mod so I have one place to count up all the interested parties. Thanks, Gerry

[LeeKirkman]

Brilliant counters Racals i have the 1991. Also have a couple of Blackstars which are a little more compact. But work well.

[gerrysweeney]

Yeah, older equipment is quite often really nicely made. I like the older HP gear for build quality, the Racal is nicely built in most places but some of it is poor - the Timebase board connector for example! Displays are a much bigger thing that vendors often under estimate. A high quality TFT can be really nice, VFD's are great apart from their ageing. Thanks for the comments.

[gerrysweeney]

Hi James, I bought them on e-bay. They are not perfect by any stretch of the imagination and the mod is quite irreversible because of the button cutting and gluing, but they are a hell of a lot better than the original crappy broken buttons thats for sure. I can't remember the exact source but the buttons you want are 6mmx6mmx10mm shaft length with two pins. I got the wrong ones I got 7mm shaft length so there was more faffing around than there should have been. Gerry

[OneCoolDude]

I just love the beauty and craftmanship in older test equipment. I much prefer an LED display over LCD (even in color).

[gerrysweeney]

I was starting to worry that people would be getting tired of frequency counter vids...I will add it to the list. Gerry

[yellowcrescent]

Connector on the xtal board and front panel looks like TE/AMP AMPUMOD 216604 Series. 10-pin is cat# 216604-4. Digikey has em for about US$3, but might be something else-- probably have to verify pin spacing on the drawing, but looks like it could be 300mils (7.62mm). Good luck!

[PapasDino]

Nice repair Gerry, great video...wish they were all that simple! Count me in for a PCB to update my Agilent 5131A with a OCXO (although I run all the boxes off the bench standard it would be nice to have a portable capability with better accuracy than the low-end oscillator). Still waiting for my Rb to arrive via slow boat from China and playing with MPLAB to program the PIC for front panel LED control.

Dino

[gerrysweeney]

Yeah, check out the review/teardown videos I done on the Keithley 2110, thats exactly what they have done - big bezel around a small crappy LCD.

[gerrysweeney]

I just watched the video and you are right 1998 - I believe that is because the 2.6GHz option board was removed, I guess thats the difference in the models then - 1998 is 160Mhz single channel, and 1999 is the 2.6Ghz dual channel. Well spotted. Gerry

[OneCoolDude]

I hope you keep cranking out videos like you have been. You're definetely in my top 3 favorite Youtube channels. SignalPathBlog has the #1 spot, sorry, lol. Maybe I just love how he refers to himself in the 3rd person, haha.

[gerrysweeney]

Yeah that counter got a fair amount of bangs and bumps during the last few months, thats why I thought I would fix it, I was starting to hurt my hand :) Gerry

[Bully]

Always look forward to your videos. I agree the oscillator upgrade would be a good video. Can you let me know where you sourced the replacement switches. Cheers

[gfsh]

Nice one Gerry another great repair and I think the oscolater upgrade would make a good video.

[OneCoolDude]

Gotta love the trend of using giant LCD and putting so many icons and menus the actual readout area is tiny, lol. The other "trick" I have noticed is they put a huge bezel around a tiny LCD to make it look big, but in reality you have a small hard to read display. My wish would be for manufacturers to use OLED displays like in the Agilent handhelds. Those are gorgeous.

[OneCoolDude]

Haha that is a perfect example. I'm a huge fan of the old brown Keithleys with the red LED display. Unfortunately my Oscilloscope broke, so I need to replace that before I can think about buying a bench DMM.

[SoddingaboutSi]

I have a dana 1998 I just bought. Its great apart for once when it gave an error 4? Is that an eprom error as in the DMM's

[OneCoolDude]

Haha yep, that is a perfect example. I'm a huge fan of the old brown Keithleys with the red LED display. Unfortunately my Oscilloscope broke, so I need to replace that before I can think about buying a bench DMM.