Repair of a Racal-Dana 1991 nanosecond Universal Counter. The push-buttons on these counters are notorious for failing and with spares not available. More over at my website - www.ianjohnston.com
Пікірлер: 34
@OneCoolDude0811 жыл бұрын
I am just thinking of down the road. I would like to see vintage test equipment to say functional for future generations to enjoy. If one of these switches go bad it will present a service challenge due to the epoxy. I actually found your channel from Gerry Sweeney. Glad to see you guys keeping these old gems alive!
@turboslag9 жыл бұрын
I have this counter too but it is yet to be afflicted with the switch problem. The issue may be related to how the counter is stored. Mine was purchase at an MOD auction and has subsequently been kept in the house. The problem looks to be a prime candidate for a 3D printing solution!
@bladerunner1147 жыл бұрын
I like that kind of instrumentation. My wish is to purchase one such as yours. I have one really old universal counter which you can see on my channel. It is Nordmende DIC 3356. That jumpin arround could not be the problem at all. Or as you said, 1kHz from your scope is probably not highly stable.
@gerrysweeney11 жыл бұрын
Thanks Ian, I bought some with a 7mm shaft length (as opposed to the 11mm you used) 261214486564. Thanks for the info, if I get around to the repair I will do a video response. Thanks again. Gerry
@jonnoxon17208 жыл бұрын
It's 11 Nov 2015 and I've got a Racal 1992 coming. Now I know how to repair the switches, should the need arise. Apparently switches are a common problem with these puppies. Thanks Ian.
@zx8401ztv9 жыл бұрын
Sorry about commenting on such an old video. I have the racal 1998 simpler frequency counter, the 10mhz reference ovan on the back panel was cooked to death, it was very old indeed, perhaps yours needs a check for stability. They are a brilliant counter for there era, and well worth the trouble of repair :-D
@IanScottJohnston9 жыл бұрын
zx8401ztv All comments are welcome. Back in the day I used a 1991 counter every day in my day job, I always found the user interface to be very intuitive and comprehensive........probably why I bought this unit for the home workshop.
@zx8401ztv9 жыл бұрын
IanScottJohnston I converted an older racal from the numerators to led display for a frend, i know its a no no but the numerators were very ill and the cost of fresh ones just didnt go down well. Yet again another very good counter. And for a laugh, ive had a maplin mf100 counter based on a big beast ICL 7xxxxx type chip, never failed though, Intersil made some dam good chips in the past, no fish though lol sorry :-(
@g1fsh11 жыл бұрын
Nice Vid mate u made a really nice job of that.
@IanScottJohnston11 жыл бұрын
This is an Ebay trick......when the seller runs out of stock they hike the price right up to stop folks buying......then when stock comes in they lower it again. This is cheaper than killing the ad completely and paying the selling fees all over again. Ian.
@IanScottJohnston10 жыл бұрын
Hi, presume you mean the lage 28-pin LED driver IC (intersil)..........Luckily, the IC was socketed so I just pulled it. If I remember correctly I think I had to snip away some of the plastic joining the 2 rows of pins to get access to the solder pads. No real harm done.
@L7pusher10 жыл бұрын
@ Gerry Sweeney I watched your video and read your comment below on Ian KZfaq channel about the switch height for the Racal-Dana 1999. Ian said he used 11mm and cut it down a little. And you said you ordered and used a 7mm switch but I remember you used two shims to raise the shaft higher. If you did it again would yo use a 9mm or something even higher? Thanks in advance. Walter
@IanScottJohnston11 жыл бұрын
Hi, I did think of that......but it was easier/quicker to mod the caps.
@douro209 жыл бұрын
What kind of reference is in this counter?
@gerrysweeney11 жыл бұрын
do you know what shaft height the switches were that you used?
@TheDefpom7 жыл бұрын
I just picked up one of these, none of the buttons work, will be doing the same replacement, I have purchased 10mm height as that seemed about right from measuring it, i will find out when I go to do it. I will do a video for my channel to show it.
@IanScottJohnston11 жыл бұрын
From what I hear the tactile switches do suffer, but how widespread those switches are used I don't know.
@gerrysweeney11 жыл бұрын
Hi Ian, I have a Racal-Dana 1999 the switches are also terrible. Which switches did you use for the repair, do you have a part number? Mine only has 14 buttons so looks easer to repair. Gerry
@benjami19535 жыл бұрын
What kind of product have you used to clean the panel and the acrylic display cover? I'm afraid to remove letters from the panel and the transparency of the acrylic.
@bobengland651910 жыл бұрын
I'm in the process of replacing the buttons on a 1992 right now. I'm curious as to how you dealt with accessing buttons S12, S13 and S14 under IC2?
@L7pusher10 жыл бұрын
@Bob England What did you end up doing with regards to the switch replacement on the Racal Dana Universal counter? I have a 1992 and have the same problem getting to the switches under the large IC. It has a socket with two lower pieces of plastic. I can remove the IC and the first layer of the socket but the lowest part of the socket is solid and still in the way. I'm not even sure why the overkill on the socket is warranted - all it seems to do is prevent one from getting to the switches to replace them. I wonder if it could be careful cut out of the way as this may be less risky than trying to de-soldier the entire socket. Please let me know what you did. Thank you. Also where did you source the switches and what part did you end up using?
@IanScottJohnston10 жыл бұрын
I cut out the plastic with the IC socket left in-situ. A nice sharp pair of sidecutters did the job.
@SirBunghole11 жыл бұрын
Does most Racal-Dana equip from this vintage suffer this problem?
@IanScottJohnston11 жыл бұрын
Gerry, I think I must have got them via Ebay........I thought it was Farnell, but a quick look through my purchase history and they are not there. Anyways, the footprint is perfect just a pity the shaft is a bit long on the ones I used. If you can get them about 4mm shorter then they'd be better. w9gb may have offered some possible alternatives at cherrycorpdotcom
@gerrysweeney11 жыл бұрын
The ones at cheerycorp do not look right. I will have a scan around on ebay. Thanks
@stazeII9 жыл бұрын
Ian: quick question. How did you "hollow out" the button tops? I tried with an X-acto, and it's crude at best. Was thinking the dremel next, but I'm worried about it wandering and chewing through the sides. Thanks!
@IanScottJohnston9 жыл бұрын
I just used a sharp pair of sidecutters.
@stazeII9 жыл бұрын
IanScottJohnston Huh. That works for the sides of the "cross", but getting the bottom out just becomes a mess. But, guess I'll give it a go on the rest. =) Thanks!
@IanScottJohnston9 жыл бұрын
I only needed to remove the cross. I think I shortened the button shafts also.
@tonydarby909611 жыл бұрын
Has the seller of the 11mm height switches spotted an opportunity, or did you really pay over £100 for them? I have ordered some of the 7mm height ones for insurance for when my counters switches give out. Tony
@w9gb11 жыл бұрын
Cherry MX or CS model switches may fit this unit.
@OneCoolDude0811 жыл бұрын
I think I would have dremeled the switch shaft to fit the button rather than destroying the button cover.
@SeanSturley8 жыл бұрын
Hi Ian, I was given one of these as a "present" from a friend of mine as it was not working, and it seems the the faulty switches appears to be the reason behind this "kind" gesture. Anyway after watching your video I was thinking I might give the button upgrade ago - I have looked around ebay for the two item numbers listed below and the are no longer listed but I have found these - www.mouser.com/ds/2/209/MS-100638-199913.pdf. Any good?
@IanScottJohnston11 жыл бұрын
Found them.....Ebay 320965040599 Not sure exactly how much I cut them down by though.