Re: [time-nuts] TAPR TICC boxed (input protection)

Hi If anybody gets into this sort of thing in the future — There are black / optical blocking die coat materials out there. They are silicone based and quite stable. We used a *lot* of the stuff on watch modules after it was discovered that the watch died when exposed to a heavy dose of

Re: [time-nuts] TAPR TICC boxed (input protection)

On Sat, 8 Apr 2017 16:30:38 -0400, you wrote: >David wrote: > >> I mentioned this in connection with some manufacturers using gold >> doping in transistors which would not normally be expected to have >> gold doping. So you end up with a bunch of lessor named 2N3904s which >> meet the 2N3904

Re: [time-nuts] TAPR TICC boxed (input protection)

On Sat, 8 Apr 2017 21:43:31 +0200, you wrote: >Am 08.04.2017 um 17:52 schrieb David: >> >> If they are not being tested, then where is the maximum specified >> leakage number coming from? For a small signal bipolar transistor it >> will typically be 25nA, 50nA, or 100nA, but the InterFET

Re: [time-nuts] Sinlge ADC multi-band receiver

On 4/10/17 2:08 PM, Eric Scace wrote: This approach is known as “security through obscurity”, and is deprecated in the professional of information security. What one invents, another can discover. The most secure systems use well-documented algorithms with open-source software — widely

Re: [time-nuts] Line Frequency Stability

Back in the 1970's I was chief engineer at a couple of local radio stations. They were automated and needed to carry network programs at the top of the hour in real time. The switching gear used electrical motors with cams and roller switches. These motors were locked to the line frequency and

Re: [time-nuts] Sinlge ADC multi-band receiver

depend how much in-band loss could you afford it is relative easy to make cavity filters if you have a network analyzer available 73 Alex On 4/10/2017 9:11 AM, Attila Kinali wrote: On Sun, 9 Apr 2017 18:13:48 -0400 Bob kb8tq wrote: The beauty of the system would be that

[time-nuts] Apr 16 MIT flea gathering of time-nuts

Are any other time-nuts planning to visit the MIT Flea market on April 16 Sunday? (So far I know of at least 3.) Contact me off-list, as we’re planning to meet for coffee/sandwiches at the nearby Flour café at noon. Even if you can’t make it, I’d like to meet you in person. Hopefully

Re: [time-nuts] Sinlge ADC multi-band receiver

This approach is known as “security through obscurity”, and is deprecated in the professional of information security. What one invents, another can discover. The most secure systems use well-documented algorithms with open-source software — widely scrutinized for bugs or implants, and

Re: [time-nuts] Re. Interesting experiments with SDR

Assuming you're in the channel islands, you should be able to pick up BBC radio 4 long wave on 198kHz, if your SDR can handle frequencies that low. It's referenced to a rubidium standard and checked by NPL. It can also be used to discipline a reference, or compared with some other local standard

Re: [time-nuts] Re. Interesting experiments with SDR

Andre Very interesting on the blue LED varicap. I'll have to see if I have one to test. If a few it would be interesting to see if they track with V/C. With respect to Island FM. The station is unclear to me but the easiest thing to do is simply call them and ask what there reference is. You

Re: [time-nuts] Sinlge ADC multi-band receiver

On Mon, 10 Apr 2017 09:00:17 -0400 Bob kb8tq wrote: > > > > Only if you *need* the Galileo E5. > > The other point with E5 is the nature of the data on the various sub signals. > Galileo has three classes of service and only one of them is free (open). Yes. Thats why we do

Re: [time-nuts] Sinlge ADC multi-band receiver

On Mon, 10 Apr 2017 07:00:27 +0200 Magnus Danielson wrote: > God Morgon Attila, > > On 04/09/2017 10:28 PM, Attila Kinali wrote: > > On Tue, 4 Apr 2017 17:58:11 -0700 > > jimlux wrote: > > > > The beauty of the system would be that you don't

Re: [time-nuts] Sinlge ADC multi-band receiver

On Mon, 10 Apr 2017 08:08:10 +0100 "David J Taylor" wrote: > Thanks for that pointer! Most interesting. I wonder whether anyone has an > updated document detailing the different systems and their current state, as > that information is approaching 10 years old?

Re: [time-nuts] Sinlge ADC multi-band receiver

On Sun, 9 Apr 2017 18:13:48 -0400 Bob kb8tq wrote: > > The beauty of the system would be that you don't need a SAW filter > > at all. If the input stage (LNA + mixer) has a high enough dynamic > > range, then the (first) IF filer alone can remove all those out of > > band

Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork crystal specs

Hi > On Apr 9, 2017, at 10:01 PM, Alex Pummer wrote: > > actually it does not compensate for temperature it is just for reduce the > production cost for the crystal. We --Jean Hoerni [founder of intersil, > Eurosil and one of the traitors who started Fairchild

[time-nuts] Re. Interesting experiments with SDR

Hi all. I found something intriguing, on at least some SDRs the 28.8MHz crystal is way off by about -2% Reset mine using Island FM to fine tune, a simple reverse biased blue LED (6pF) to tweak the centre frequency a bit and now my 1990 vintage Black Star counter and SDR agree correctly.

[time-nuts] 32768Hz oscillator using AT-cut crystal

Now, this is neat, and I'm not surprised that it's manufactured by Seiko. A 32768Hz oscillator chip that uses a 16MHz-range AT-cut crystal for a completely different temperature curve than you'd get from a tuning fork crystal: http://www.npc.co.jp/en/news/release/2012/11/28/78/ The principle of

Re: [time-nuts] Sinlge ADC multi-band receiver

Hi, On 04/10/2017 03:00 PM, Bob kb8tq wrote: Hi On Apr 10, 2017, at 1:00 AM, Magnus Danielson wrote: God Morgon Attila, On 04/09/2017 10:28 PM, Attila Kinali wrote: On Tue, 4 Apr 2017 17:58:11 -0700 jimlux wrote: The beauty of the

Re: [time-nuts] Sinlge ADC multi-band receiver

Hi Bob, > It is a bit unclear what the third > band would add other than a "cool factor" Even quicker RTK convergence. http://www.navipedia.net/index.php/Carrier_phase_ambiguity_fixing_with_three_frequencies -- Björn ___ time-nuts mailing

Re: [time-nuts] Sinlge ADC multi-band receiver

Hi > On Apr 10, 2017, at 1:00 AM, Magnus Danielson > wrote: > > God Morgon Attila, > > On 04/09/2017 10:28 PM, Attila Kinali wrote: >> On Tue, 4 Apr 2017 17:58:11 -0700 >> jimlux wrote: >> >> The beauty of the system would be that you don't

Re: [time-nuts] Line Frequeny Stablity

Several years ago (c. 1980) I remember an occasion when the local utility slipped about 20-25 minutes of effective 'time' over the course of one night. I didn't know much about power grids then, except that they existed, and contributed to certain power blackouts. But what happened was that the

Re: [time-nuts] Sinlge ADC multi-band receiver

BTW: Rodriguez' PhD thesis[2] (which is the basis of navipedia) gives a very nice overview of the trade-off's that went into the Galileo signals and gives a few hints where future GNSS signals could further improve things. Attila Kinali [2] "On Generalized Signal Waveforms for Satellite

Re: [time-nuts] Sinlge ADC multi-band receiver

God Morgon Attila, On 04/09/2017 10:28 PM, Attila Kinali wrote: On Tue, 4 Apr 2017 17:58:11 -0700 jimlux wrote: The beauty of the system would be that you don't need a SAW filter at all. If the input stage (LNA + mixer) has a high enough dynamic range, then the (first)

Re: [time-nuts] Sinlge ADC multi-band receiver

Hi Attila, On 04/09/2017 10:29 PM, Attila Kinali wrote: On Wed, 5 Apr 2017 10:37:07 +0200 Magnus Danielson wrote: Also, you don't really need to keep the bands fully separate in their mixed-down form, since they do not correlate except for the P(Y), but keeping

Re: [time-nuts] Sinlge ADC multi-band receiver

> On Apr 9, 2017, at 4:29 PM, Attila Kinali wrote: > > On Wed, 5 Apr 2017 08:27:58 -0400 > Bob kb8tq wrote: > >> Galileo E5 is a bit of a strange case. It’s really E5a and E5b. >> You can either grab it all as one giant signal or as two separate signals. >>

Re: [time-nuts] Sinlge ADC multi-band receiver

HI > On Apr 9, 2017, at 4:28 PM, Attila Kinali wrote: > > On Tue, 4 Apr 2017 17:58:11 -0700 > jimlux wrote: > >>> The advantage of such a system would be that there is only a single >>> path through the system for all signals, especially through the