[time-nuts] From Burt - K6OQK...
Gang, I became aware that I had not been getting anything from the time-nuts list. Apparently I somehow fell off the list. I just re-subscribed and hope things will get back to normal for me. Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Connector options for HP10811A?...
Frank, Can you send me a picture of the connector? Are you familiar with APEX (Surplus) Electronics in Sun Valley. The sometimes have unusual connectors. The problem is, you may have to look through the place for it. The good news is that they can tell you where to start looking. me At 06:39 PM 4/8/2020, you wrote: I recently bought an HP10811A oscillator on eBay, only belatedly realizing that it's designed to interface to a 15-contact connector that the manual identifies as a CINCH 250-15-30-210 or equivalent. A search turns up a vendor in Massachusetts called BMI Surplus Inc., that appears to have these in stock in new condition at a minimal price. The only hitch is that BMI's website says they're closed down due to COVID-19 and will not process any orders until their state government authorizes businesses to return. (And at this point, it's anyone's guess when that will be.) To get going with the oscillator, it occurs to me that I could rig up a few small alligator clips and use them on the required contacts for the time being. Any other thoughts or suggestions on how to work this? By any chance are there other known sources for the right size of connector that might be operating right now? Thanks much, Frank O'Donnell South Pasadena, California ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Vaperware Parts and pulse stretching circuits
John, What you and I do for SMT type IC's is pretty much the same. Several years ago the wife of a close friend was in the re-work business with a home setup. What she taught me was to first line up one of the corner pins and tack solder it down. Then do the opposite corner, center the pin and tack solder it down. Do that with all four corners, taking care that the pins are properly centered before tack soldering them. Once you've got the four corners properly in places, then go and center the remaining pins; depending on the size of the chip, this might require either a microscope or very pointy eyes. Once all the pins are properly centered, flow solder over all the pins. At this point shorting all the pins together is not a problem. Once you've flowed soldered across all of the pins you need to slurp up all of the solder with a fine pitch SolderWick. If done correctly you will wind up with all of the pins properly soldered and centered. The next step is to remove and flux using Denatured Alcohol. Once that's completed, inspect for any possible shorts or pins in the wrong place. If all looks good, cover your eyes and power it up. I have done the above one time on my own and to my utter amazement it worked! Burt, K6OQK At 04:41 AM 4/25/2020, you wrote: I do have a microscope (cheap Chinese unit, maybe $400 with articulated arm and the works) and it does make things much easier. But as long as you can see the work, you can do the job. It's not that hard to do small pitch parts. I usually do the best I can soldering individual pins, knowing their will be bridges, then clean up with solder wick and *lots* of no-clean flux. You can never have too much flux. I've found a 1.6 mm chisel tip is a good all around size for SMD work, though I have a 0.8 mm chisel available for when things get tight. The hardest part is getting the first couple of pins tacked down so the part is square on the pads Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Soldering small stuffs...
I have an AM-SCOPE 7-35 magnification stereo microscope. I also have an OptiVisor with a 5x stereo lense that my son gave me about 10 years ago. As nice as the microscope is, I generally wind up using the OptiVisor. I have to agree with you about trying to solder under a microscope. It take a lot of practice. Burt, K6OQK At 05:38 PM 4/25/2020, Bill Notfaded wrote: I bought some magnifying glasses with 5 sets of different power lenses you wear like glasses. It has built in led light and adjustable strap that hold it on your head off Amazon. Works great. I can do all small surface mount stuff with them. Plus I have my normal vision and hand eye coordination going that way. Soldering under a scope or on a video monitor is a lesson all in itself! Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Time Interval Counter(?) for high-precision watch measurement...
A friend of mine sets watches this way, except that he slips the watch into a coil connected to his HP-3586B SLM receiver. This seems to work even with metal cased watches. Burt, K6OQK At 07:57 AM 9/9/2020, you wrote: The 32768 Hz crystal oscillator can be received, amplified, and filtered outside the watch as described here: http://charliethompson.50megs.com/quartz.html I actually tried this once, and it worked quite well on every watch and clock I could get my hands on at the time. The first three transistors form an amplifier with around 100 dB of gain. The crystal filter is required to remove the broadband noise generated by the amplifier. I didn't include the final two transistor "squaring" output stage because I was interested in having a sinusoidal output to view on a scope. 73.000 de John, KD2BD ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
The 45 degree phase shift was a form of identification for WWVB and also served as a marker for chart recorders. The shift occurred from 10-minutes past the hour until 15 minutes past the hour. Before GPS came along, WWVB was my main frequency standard/reference. I had two Gertsch RLF devices and a "thumper" chart recorder. It was really a lot of grief trying to keep my relatively poor crystal oscillators on frequency. If I was able to see the 45-degree shift I felt as though I was really accomplishing something. :] I now have two DATUM 9390-52054 GPS units. GPS has really spoiled me! Up until the phase shift was added I used a Symmetricom 8170, not so much as a frequency reference, but as a clock in my shoppe. The 8170 is still running, but displays some strange combination of numbers that actually tell me the status of it trying to set. I suppose I should build a de-psk-er thingy, but I lost the paper work on how to do it.The 8170 presently serves as a night lite. Burt, K6OQK At 08:36 AM 10/4/2020, someone wrote: Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > that shows up as time-tags on the strip-chart, so it is not trivially... Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net K6OQK ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.