the other?
> Bob
> -
> AE6RV.com
>
> GFS GPSDO list:
> groups.yahoo.com/neo/groups/GFS-GPSDOs/info
>
> From: Didier Juges
> To: Bob Albert ; Discussion of precise time and frequency
> measurement
> Sent: Thursday, August 11, 2016 1:20 PM
> Subject: Re:
st 11, 2016 1:20 PM
>Subject: Re: [time-nuts] Safely getting the electrical length of a
>connected antenna feedline
>
>I used the PPS from a Thunderbolt (fast rise lime, low rep frequency,
>was handy) and a digital storage scope and a couple of resistors to
>make a reflectometer
"The biggest variable will be the velocity factor."
If you determine the length electrically, you will already have the
electricallength. If you need the physical length, then multiply electrical
length times the inverse of the velocity factor.
--
Joe Leikhim
Leikhim and Associates
Communi
To: Bob Albert ; Discussion of precise time and frequency
measurement
Sent: Thursday, August 11, 2016 1:20 PM
Subject: Re: [time-nuts] Safely getting the electrical length of a connected
antenna feedline
I used the PPS from a Thunderbolt (fast rise lime, low rep frequency, was
handy)
I used the PPS from a Thunderbolt (fast rise lime, low rep frequency, was
handy) and a digital storage scope and a couple of resistors to make a
reflectometer based on this experiment:
www.ko4bb.com/getsimple/index.php?I'd=coax-cable-impedance-matching
You can very clearly see a 50 ohm/75 ohm m
You left out the obvious time-nut solution: Calibrate and characterize an
ensemble of HP5071A's to correct absolute time at NIST. Transport the
ensemble (correcting, if necessary, for general relativisitic effects) to
your house. Set the cable delay in your GPS receiver to zero. The delta
between y
Thanks David. I have ordered some from ebay, very cheap.
5pcs SO/SOP/SOIC/SSOP/TSSOP/MSOP14 to DIP 14 Adapter PCB Board Converter MA
| |
| | | | | | | |
| 5pcs SO/SOP/SOIC/SSOP/TSSOP/MSOP14 to DIP 14 Ad...US $1.32 New other (see
details) in Business & Industrial, Electrical & Test
These are a little larger than what I was thinking of but were
mentioned the other day in funwithtu...@yahoogroups.com and are
probable more suitable for most projects anyway:
http://qrpme.com/?p=product&id=MEP
On Tue, 9 Aug 2016 16:10:38 + (UTC), you wrote:
>Yes, a board with the required f
Hi:
Another option is so Google for a "Breakout board" for the IC you're looking to work with. People like Spark Fun, Seed
studio, &Etc make these.
It's a board that holds the chip and the needed accessory parts, but needs
something else like an Arduino.
--
Have Fun,
Brooke Clarke
http://ww
On Tue, Aug 9, 2016 at 9:10 AM, Bob Albert via time-nuts
wrote:
>
> Yes, a board with the required footprint would be the way to go. Where does
> one find that?
You can have small PCBs made for $3 each.
There are places here in the US that will do PCBs for $3/square inch
with a one square inch
Yes, a board with the required footprint would be the way to go. Where does
one find that?
On Tuesday, August 9, 2016 12:00 AM, David wrote:
Richard mentioned the SMD to leaded adapters which work well.
Another way which is more suitable for Manhattan or dead bug type
construction is
From: Dr. David Kirkby (Kirkby Microwave Ltd)
I thought i might be possible to do this with a VNA, and a test antenna
located a known distance apart. So I asked in the Keysight forum on 8th Feb
2015
[]
Dave
___
Folks,
Yes, I've used the DG8SAQ Vector
If you have *the* active antenna, it is pretty easy to
make a little quadrapole circularly polarized antenna out
of a couple of pieces of 141 semi-riged coax, and to transmit
signal into the active GPS antenna, and measure the signal
coming out of the active GPS antenna.
If you don't have the actu
On 8 Aug 2016 21:23, "Bob Camp" wrote:
>
> Hi
>
> An even more significant question:
>
> Is it worth doing?
> Your antenna and module could easily have delays
> in the 40 ns range. It has no impact on a “frequency” GPSDO. It is one of
a number of static offsets in a time transfer system.
>
> Even
I doubt it's worth mentioning that a random SMD footprint cut from a larger
board and some of the currently available eBay SMD adapter boards may have
plated through holes which could short if used to prototype on copper clad
board so it's worth paying a little attention to insulating the
'undersid
Richard mentioned the SMD to leaded adapters which work well.
Another way which is more suitable for Manhattan or dead bug type
construction is to glue or solder down just tiny printed circuit board
which has the SMD footprint and then solder directly to the leads or
extensions to the pads. This
n dip.
73, Dick, W1KSZ
-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Albert via
time-nuts
Sent: Monday, August 08, 2016 8:37 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Safely getting the electrical l
You could get a low cost GPS unit and compare the PPS from it to the PPS from
your setup with the long cable.
Modern GPS receivers are sensitive enough to work with a poor antenna
(indoors) and don't cost much.
--
These are my opinions. I hate spam.
__
Gate drivers are pretty zippy when you leave out the capacitive load of a
power fet's gate. They are also available in 8 pin dip.
On Monday, 8 August 2016, Bob Albert via time-nuts
wrote:
> Your comments on layout made me think again of how to implement these
> projects. How do you use a 14 pin
of precise time and frequency measurement
Subject: Re: [time-nuts] Safely getting the electrical length of a connected
antenna feedline
Your comments on layout made me think again of how to implement these projects.
How do you use a 14 pin SMD IC? I could try to connect it with flying leads
bu
Your comments on layout made me think again of how to implement these projects.
How do you use a 14 pin SMD IC? I could try to connect it with flying leads
but I'd like something better. Is there some kind of socket for these devices?
Or a generic board to receive such things?
Bob
On
I actually tested various 74120 dual 4-input NAND drivers which
produce the sync output on my B&K function generator to find ones
which would provide the fastest and cleanest pulse. AS (advanced
schottky) and FAST (fast advanced schottky TTL) were the best for me.
Modern inexpensive discrete logic
First, the nulls are sharper than the peaks. What you do is measure the
frequency of adjacent nulls and calculate what frequency makes both of those a
half wave or multiple thereof. Then you know the number of half waves to the
mismatch. It's the distance from the tee to the remote end.
It ta
ewart"
To: "Discussion of Precise Time and Frequency Measurement"
Sent: Monday, August 08, 2016 2:18 PM
Subject: [time-nuts] Safely getting the electrical length of a connected
antenna feedline
Earlier this year, with some help, I pulled the dish off of an old DishTV
antenna on t
/GFS-GPSDOs/info
From: Bob Albert
To: Bob Stewart ; Discussion of Precise Time and Frequency
Measurement ; Discussion of precise time and frequency
measurement
Sent: Monday, August 8, 2016 2:18 PM
Subject: Re: [time-nuts] Safely getting the electrical length of a connected
antenna feed
rt ; Discussion of precise time and frequency
measurement
Sent: Monday, August 8, 2016 3:14 PM
Subject: Re: [time-nuts] Safely getting the electrical length of a connected
antenna feedline
Hi
An even more significant question:
Is it worth doing?
More or less:
Do you know the delay numbers
Hi
An even more significant question:
Is it worth doing?
More or less:
Do you know the delay numbers for your antenna?
Do you know the delay numbers for your GPS module?
How close can you *guess* the length of the cable?
Knowing absolutely nothing at all about your setup, I’ll guess the ca
I host a group called something like HF Antennas. There I posted a link to an
article on how to measure coaxial cable. The easiest way is with a spectrum
analyzer and a tracking generator.
You connect the generator to the analyzer through a Tee that goes to the
unknown coax. You will see a gr
b...@evoria.net said:
> Earlier this year, with some help, I pulled the dish off of an old DishTV
> antenna on the roof and put a 5V bullet antenna on the mast. I also pulled
> a new cable through by attaching it to the old one. The problem is that I
> was not able to measure the new cable. So,
Earlier this year, with some help, I pulled the dish off of an old DishTV
antenna on the roof and put a 5V bullet antenna on the mast. I also pulled a
new cable through by attaching it to the old one. The problem is that I was
not able to measure the new cable. So, the question is, without go
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