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Re: How to calibrate a frequency counter (on the cheap)
Thanks for all of the very helpful replies! What about a non-Thunderbolt GPS receiver that only outputs a 1 pps signal and has no provision for a 10 MHz output? For example, a receiver that has
By honolulusnowwhite · #82054 ·
Re: How to calibrate a frequency counter (on the cheap)
I asked about this not long ago on the time-nuts@... mailing list. Most receivers have a fixed frequency oscillator driving the numerically control oscillators so the 1pps output has significant
By David Hess · #82053 ·
Re: How to calibrate a frequency counter (on the cheap)
Usually the 1 pps comes from the 10 MHz (or some higher reference) but they are both common. Tom
By Tom Miller · #82052 ·
Re: How to calibrate a frequency counter (on the cheap)
If I understand correctly, the 20nS spec. of the 1ppS signal is relative to time, not frequency, in other words, it means that the 1 ppS pulse is within 20nS of GPS (I think) time once the delays are
By Geoff Blake <geoff@...> · #82051 ·
Re: How to calibrate a frequency counter (on the cheap)
After seeing this post, I looked into the specs of various GPS receivers. I note that the Thunderbolt is rated at 1 part in 10^12 accuracy with respect to the 10 MHz signal that it produces - can't
By honolulusnowwhite · #82050 ·
Re: 7B92 No Auto trigger
I have no clue. They are in a bin marked something like "5V T-1" and when tested were more like 75mA instead of 60mA. The place is Gateway Electronics near St. Louis but they do not have them listed
By David Hess · #82049 ·
Re: 7B92 No Auto trigger
The Mouser lamps are rated for 100k hours. What are the ones you found rated for? Tom
By Tom Miller · #82048 ·
Re: 7B92 No Auto trigger
For the 5 volt T-1 lamps Tektronix used for their illuminated switches, these are what I was going to order until I found a less expensive supply of them at a local electronics store:
By David Hess · #82047 ·
Re: 7B92 No Auto trigger
Thanks for your suggestions. I will check them and post back as soon as I have a chance (probably later tonight). I can't believe how much time I'm spending on this plug in, but it's so close to
By Andy · #82046 ·
Re: two 453 scopes for sale
It would be nice if EVERYBODY?would ALWAYS remember to include their location in their "have" listings. It's a little frustrating for us stateside folks; a lot more so for people in Europe. 73 Jim
By Jim <n6otq@...> · #82045 ·
Re: 7B92 No Auto trigger
pdf page 26, calibration steps j and k. Albert
By Albert <aodiversen@...> · #82044 ·
Re: 7B92 No Auto trigger
(continued) Hi Andy, I think I addressed your last message also, actually I saw too late that I replied to a new message from you. Albert
By Albert <aodiversen@...> · #82043 ·
Re: How to calibrate a frequency counter (on the cheap)
There's a HK based ebay seller who does a Micro Crystal OXCO in a 14 DIP package, see item #310380778466 - just over $25. I put one of these in a 1991 that had a faulty TCXO and it seems pretty good.
By nowtotallyhackedoff · #82042 ·
Original Manual - free
5030 Dual Beam Scope Instruction Manual in Excellent condition - Free to a good home All you pay is for the package and the shipping cost to CONUS only. Contact me off list please Chris HJ
By Christopher Hilton-Johnson · #82041 ·
Re: 7B92 No Auto trigger
Hi Andy, My previous comments need correction. I did measurements now in my 7904A and in this 'scope the whole trace intensity was influenced by the plugin's pot. Then I saw and remembered a jumper
By Albert <aodiversen@...> · #82040 ·
two 453 scopes for sale
Hi, I have two type 453 scopes for sale both do not work but are good for parts. I asking $35 for each one and actual shipping. pics avalable on request thanks Jon
By Jon · #82039 ·
Re: Beautiful 556 setup on Ebay
I guess we are lucky he understed the qunatity. The 556 uses 17 6DJ8 tubes, not 12. It went fast - hopefully to someone who appreaciated it as a scope. Too bad I did not see it in time - I have a good
By ditter2 · #82038 ·
Re: Who Bought the 1L20 on eBay?
Bummer.? How about using one of these: http://www.ebay.com/itm/HP-8445B-Automatic-Preselector-/280977359914?pt=LH_DefaultDomain_0&hash=item416b8e442a (no connection to seller - just an example of a
By Daniel Koller · #82037 ·
Re: 7B92 No Auto trigger
Hi Albert, It's good to know the intensity problem may not be significant. I'll ignore it for now. I tried what you suggested, and discovered that the delayed trigger has other problems. The delayed
By Andy · #82036 ·
Re: Interesting fault in 535A
Sorry, Morris, I didn't notice where you were. Carry on. Dave Wise
By Dave Wise · #82035 ·