Hello Chris, I've been reading all about your very neat dekatron freq. counter! The pending troubles with the aging 6909s is an interesting one, and congratulations on your recent Ebay purchase of a fast 6909 for the "ones" position.
This reminds me somewhat of a much later freq. counter I have that I bought at a hamfest some years ago. It was outside, in the parking lot, at the huge Orlando, FL hamfest. This guy had tons of old test equipment stacked on the ground and I spotted a few pieces that had nixie readouts in them. I bought a few of those pieces basically for scrap value and paid $2.50 each for a few of the smaller pieces of test equipment, and I also paid a hefty $5.00 for this CMC 12-digit nixie tube freq. counter. Originally I was just going to scrap the counter to get the NL-5853 nixies, and their old Fairchild driver ics. But, before I started scrapping it, just for the heck of it I powered it up, and, amazingly it started working straight away!! It's only problem was that somewhere along the line it turned up missing its left-most tube in the readout. That was an easy fix, I just dug out a NOS NL-5853, and put it into the socket. The driver ic was still there. This freq. counter, made by CMC, looks to be made sometime in the early 1960s. It has a crystal oven, and once warmed up, it is amazingly accurate! Needless to say, I never had the heart to scrap it. It works! It only triggers and operates reliably though if it is fed a nice square wave. It does not do very well with a sine wave, nor much of any other waveform, for that matter. Anyone out there know if this is a common trait of these old counter-timers? Great work on the dekatron frequency counter though! You are very lucky and fortunate to own it. Chuck > > >---- Original Message ---- >From: [email protected] >To: [email protected] >Subject: RE: [neonixie-l] Re: Dekatron frequency counter and 6909 >issue >Date: Sun, 23 Jun 2013 09:29:13 -0700 (PDT) > >> >>"Phantastrons" >> >>What a awesome name. I believe that is exactly what the circuits >are. >> >>I got in my new 6090. Its a Sylvania 6909 but has different layout >of logo >>and has PAD on it. It looks completely NOS but no box. >> >>I put that into the ones posistion as I can fully test its top >counting >>speed there. Right away I reached 181khz before its sputtered out. >It was >>of course not reliable at that speed. It does look like I can hit >150khz >>now reliably but I will burn it in and test more. I will determine a >top >>speed where it does not miss a single count. It appears how fast it >can >>count is related to its eventual failure. So as it fails it gets >slower. >> >>I moved my other good sylvania 6909 into the 10's position where its >max >>speed will need to be like 15khz. >> >>I still need to adjust the voltages for the new tube, but this is a >>impressive top speed right away. >> >>I also need to correct something i said in a previous post. There is >getter >>on the Raython tube, the bad one, its all around the counting pins >on the >>inside of the tube. The Sylvania tubes, the good ones, do not have >any >>anywhere on them. >> >>-- >>You received this message because you are subscribed to the Google >Groups "neonixie-l" group. >>To unsubscribe from this group and stop receiving emails from it, >send an email to [email protected]. >>To post to this group, send an email to [email protected]. >>To view this discussion on the web, visit >https://groups.google.com/d/msgid/neonixie-l/5535459e-2ed2-4d1e-aa15- >833f94b780f7%40googlegroups.com. >>For more options, visit https://groups.google.com/groups/opt_out. >> >> >> $4.95/mo. National Dialup, Anti-Spam, Anti-Virus, 5mb personal web space. 5x faster dialup for only $9.95/mo. No contracts, No fees, No Kidding! See http://www.All2Easy.net for more details! -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/380-220136023171635647%40all2easy.net. For more options, visit https://groups.google.com/groups/opt_out.
