I have an HP VTVM and when I first got it, the range switch seemed erratic. I made the mistake of liberally applying De-Oxit to the switch and boy, it got really erratic after that. It took 2 or 3 days of leaving it outside in the summer sun to get the switch to dry out and it's been great ever since but a very little bit goes a very long way. I learned about De-Oxit from an HP service guy only back then it was called Cramolin and came in a small bottle as a liquid. He would take a wooden Q-Tip, dip it in the bottle and brush it on computer card edge contacts, and then wipe it off! He claimed you only needed the very thinnest of films to insure a good contact. I thought he was BS'ing me but have since learned my lesson..... Steve KD2ED In a message dated 12/23/2011 10:19:00 P.M. Eastern Standard Time, wa2...@gmail.com writes:
In addition to the "wooden stemmed tightly woven Q tips that are made especially for electrical cleaning" mentioned by Dennis, AE6C, I also use the brushes listed below. A drop of DeoxIT on either goes a long way. These brushes are great for cleaning 7 & 9 pin tube sockets: _http://www.gumbrand.com/interdental-brushes/products/gum-go-betweens-proxab rush-cleaners-wide/872rn/_ (http://www.gumbrand.com/interdental-brushes/products/gum-go-betweens-proxabrush-cleaners-wide/872rn/) These brushes are good for cleaning RCA connectors, 8 pin and other larger tube sockets, etc: _http://www.mcmelectronics.com/product/CAIG-LABORATORIES-AB-50-/200-288_ (http://www.mcmelectronics.com/product/CAIG-LABORATORIES-AB-50-/200-288) Ken WA2LBI On Fri, Dec 23, 2011 at 13:06, Dennis Monticelli <_dennis.monticelli@gmail.com_ (mailto:dennis.montice...@gmail.com) > wrote: I have found that 100% DeOxit dries more slowly than the 5% stuff because the latter is mostly carrier. So allow a little extra time before powering up, especially with pots. A few hours should have been enough, so it seems that you applied too much. I almost always use the 100% stuff but I avoid droplets. Instead I apply the DeOxit to one of those wooden stemmed tightly woven Q tips that are made especially for electrical cleaning. The Q tip then does double duty of applicator and scrubber. This works really well for wafer switches and tube pins. For socket pins, I use a wooden toothpick that is coated with DeOxit. Once again it serves as applicator and scrubber. The Q tip and toothpick end up with a satisfying dark coloration of oxides with this method. Sufaces will glisten after cleaning but you won't see any red pooling. With DeOxit a little goes a very long way. Mild scrubbing with a rough absorbant surface such as wood or tightly woven Q tip physically removes the dissolved oxides. Dennis AE6C On 12/23/11, _yash@aol.com_ (mailto:y...@aol.com) <_yash@aol.com_ (mailto:y...@aol.com) > wrote: > Today I put a totally dead R-4a on the bench,replaced the fuse and off she > went. The rig was fairly clean considering its age. The rig lit up and got > some audio out and all functions seemed to basically work. Cleaned the > chassis of dust ,damp cloth and proceeded to pull all the tubes and > test,all were good. I took a emery board and cleaned all tube pins then > wiped the pins with Deoxit and dried with a cloth, also cleaned all the > wafer switch contacts with deoxit,using the tiny needle bottle being VERY > careful to keep the deoxit to the very small amount, also cleaned all the > pots with the deoxit spray for pots. > Any way let the rig sit for a few hours working all the switch's and > pots. Reassembled the rig and powered up. The radio lite up and that was > about all ,nothing seemed to work, rechecked the tube install,all correct, > put back on the bench flipped the rig over and ALL the tube sockets and > wafer switch's looked like they were flooded with deoxit. I was careful to > use as Little as you could of the deoxit,while cleaning everything. I then > proceeded to clean EVERYTHING with 100 %alcohol, tube pins,sockets, all > wafer switch's and pots,made sure everything was dry, using a hair drier. > Put the rig back together and turned on,the R4A works as well as my B line > receiver,even without a alignment. > Has there been a change in Deoxit? I have used this procedure on lots > of Boat anchors and up till now always worked fine. Can't believe the TINY > amount I used, crawled all over everywhere I didn't want it to go. Unless > someone else had used some other substance to clean before me and the the > deoxit ,I haven't got a clue. Anyone else run across anything like this? The > deoxit was brand new a week ago. I think I will star with the 100% > alcohol,like I used to use. > everybody have a Merry Christmas > dale wt4t > _______________________________________________ Drakelist mailing list _Drakelist@zerobeat.net_ (mailto:Drakelist@zerobeat.net) _http://mailman.zerobeat.net/mailman/listinfo/drakelist_ (http://mailman.zerobeat.net/mailman/listinfo/drakelist) _______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
_______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
