Are 4 and 5 regulated? Or is the zener picked to compensate for the VBE
drops?
Any of these circuits where the output transistor is in an emitter
follower configuration will have its noise effected by the load current,
since that current directly effects the output transistor
rickhar...@gmail.com said:
I would like to triangulate a position of a device which moves using 3 fixed
positions devices of known location. The idea is to have these operate on
915mhz or 434mhz or 2.4ghz or appropriate frequency.
I'd like a range of 150 feet or better and accuracy of 3
and even a more crazy idea: use a phasing array for the directional antenna.
On Fri, Feb 1, 2013 at 10:45 AM, Hal Murray hmur...@megapathdsl.net wrote:
rickhar...@gmail.com said:
I would like to triangulate a position of a device which moves using 3
fixed
positions devices of known
Also the fixed stations can not have OCXO?
On Fri, Feb 1, 2013 at 5:37 AM, Rick Harold rickhar...@gmail.com wrote:
To time experts/EE's.
I would like to triangulate a position of a device which moves using 3
fixed positions devices of known location.
The idea is to have these operate on
Hi Rick,
You would do better putting a small GPS receiver in the mobile and transmit with
a 2.4 GHz Blue tooth transmitter. The GPS devices can be gotten very small
(your
thumb would just about cover it up). They are also very light and draw very
little power. That would save you two
Hi Rick,
You would do better putting a small GPS receiver in the mobile and
transmit with
a 2.4 GHz Blue tooth transmitter. The GPS devices can be gotten very
small (your
thumb would just about cover it up). They are also very light and draw
very
little power. That would save you two
Bob Camp, Thursday, January 31 11:36 AM (Local NY time):
((...snip...))
With a good enough voltmeter you could carry the analogy one step further
and compute an ADEV like number on the output voltage. I suspect that's
carrying things a bit far.
No, I disagree. That's not carrying things nearly
Hi Bert,
No need to block the DC. These instruments already have DC blocks (and a
switchable low current DC sink to hold the line from the exchange) because
the telephone line has a DC voltage of typically 48V on it already.
For comparison I just use 600 ohm termination and dBm, dBmV can be
Hi
The circuit I described, is (as stated) quiet down to 100 Hz. It's 3 db
bandwidth is well below 10 Hz with the 47 uF cap. If you need it quiet down to
10 Hz or 0.1 Hz, you will need to buy a few more caps. It's still not
rocket science.
For most OCXO or atomic standard testing
Linear Technology application note 83
Performance Verification of Low Noise, Low Dropout Regulators
holds some interesting information. I am however unsure whether what was low
noise in 2000 is still low noise in 2013
Best regards
Ulrich Bangert
-Ursprungliche Nachricht-
Von:
Hello, interesting discussion about noise.
It's all way over my knowledge, so my contribution
to discussion maybe is only noise :)
Re batteries I agree with Mark, see below:
Il 2013-01-31 06:42 Mark Sims ha scritto:
A123 20Ah LiFePO4 cells have an internal resistance in the milliohm
range.
I was just surprised it locked at that speed. I figured a handheld unit would
not be able to lock at that speed. Looking back on it now, it makes sense it
shouldn't have too much trouble. (Once I learned it worked I started to ask
about the GPS more. If you ask politely, a lot of times they
Joe,
I'm using that in my low power (150ma) supplies. I add a zener to the base
(darlington) circuit for pre-regulation. Since I'm doing a line operated linear
supply the fall off of gain with frequency is not of too much concern.
Once I finish testing (I have boards in hand - I need to order
On 1/31/13 1:09 PM, Chris Albertson wrote:
I know for sure my handheld Garmin works at 27000 feet, at
530mph... ...I was actually surprised it worked up there.
It made me wonder what the actual limits are.
What are the limits of your hand held unit or what are the limits of
GPS in general.
Hi
If you use an electrolytic cap on the base (tantalum or what ever) the
leakage current will mess up the output a bit. It does *eventually* die down
some, but you may have to wait for days...
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]
Can the base stations be interconnected via cable?
In that case, wouldn't it suffice to have the mobile device send an
unmodulated carrier of low enough frequency, and compare the phase
between the receiving base stations, taking the (known) cable delays
into account?
Cheers
Stefan
Rick
On 1/31/13 8:37 PM, Rick Harold wrote:
To time experts/EE's.
I would like to triangulate a position of a device which moves using 3
fixed positions devices of known location.
The idea is to have these operate on 915mhz or 434mhz or 2.4ghz or
appropriate frequency.
These two type of devices
Just to make sure I understand the 'ground rules', the three base stations
define a plane, unless they are on the same line. Is the mobile device also
in this plane? How far apart are the base stations relative to the location
of the mobile device? Or, better, is the mobile device 'inside' this
89700 dana and the srs700 has been locked for 10 hours plus. Looking pretty
good comparing RB adjusted to gps and 20ns drift will be at least 42
minutes. But just relooked at the drift and it may be much longer. SN in
Boston 49db gain 33db margin.
HP 3801 is warming up for a direct comparison.
Still locked onto the Dana/Seneca Loran stations at 8:38 am local.
Comparison to GPS/DO is about the same. No new slaves detected.
Stan, W1LECape Cod
On 2/1/2013 12:30 AM, Stan, W1LE wrote:
Fired up the SRS FS700 and auto found the GRI 89700 microsecond
stations in Dana Il (master)
and
ITAR limits are AND. If it is below 50,000 ft OR below 1000 knots, it
will work.
My Garmin GPS60CSx has always worked on commercial flights at 40,000 ft
and 500 MPH. We use commercial Trimble units on our scientific balloons
that go up to 120,000 ft (38 km).
David McGaw
NASA BARREL
What are those folks flying GPS on CubeSats using?
I do believe they roll their own. Did ask Tom Clark K3IO at the
Orlando AMSAT convention this year about the exact topic you gentlemen
are discussing. His comment was that there was only the Scud Rule to
deal with.
Norm n3ykf
Ok, but open loop as I described?
I bicmos design, there are two common junk buffers. The junkiest (sp?) is
going up a PNP and down a NPN. No feedback. You live with the vbe mismatch.
Next up the food chain is the long tail pair (diff amp) with emitter follower.
With one gain stage, it is
Hello to the group. There is no need for slaves. Quite a while ago there
was a slave but it was simply the master faking out a slaves position by
delay. That said yes indeed the systems settling in well to the RB ref and
I will switch over to the 3801 sometime this afternoon.
Fired up the Austron
On 2/1/2013 3:45 AM, Hal Murray wrote:
rickhar...@gmail.com said:
I would like to triangulate a position of a device which moves using 3 fixed
positions devices of known location. The idea is to have these operate on
915mhz or 434mhz or 2.4ghz or appropriate frequency.
I'd like a range of
Anyone locking on Wildwood, NJ - they are still fired up.
Bill, WA2DVU
Cape May
89700 dana and the srs700 has been locked for 10 hours plus. Looking pretty
good comparing RB adjusted to gps and 20ns drift will be at least 42
minutes. But just relooked at the drift and it may be much longer. SN
Yes indeed I can see the local RB and GPS along with the eLORAN all
starting to track and the local offsets are steadily decreasing. Great to
see. SURE as heck beats the ole WWVB.
Will guess long about 5pm local eLORAN will drop for the weekend. It needs
a beer.
Paul
On Fri, Feb 1, 2013 at 11:09
See my comment above
On Fri, Feb 1, 2013 at 11:23 AM, Bill Riches bill.ric...@verizon.netwrote:
Anyone locking on Wildwood, NJ - they are still fired up.
Bill, WA2DVU
Cape May
89700 dana and the srs700 has been locked for 10 hours plus. Looking pretty
good comparing RB adjusted to gps
By the way I am calling it eLORAN but I think UrsaNav has another name for
it.
Regards
Paul
On Fri, Feb 1, 2013 at 11:28 AM, paul swed paulsw...@gmail.com wrote:
See my comment above
On Fri, Feb 1, 2013 at 11:23 AM, Bill Riches bill.ric...@verizon.netwrote:
Anyone locking on Wildwood, NJ -
Content-Type: text/plain; charset=ISO-8859-1
In message 2bf4f4e8c8207ae0f94a7e1a1e63c...@quipo.it, Fabio Eboli writes:
Il 2013-01-31 06:42 Mark Sims ha scritto:
A123 20Ah LiFePO4 cells have an internal resistance in the milliohm
range. [...]
Low internal resistance in batteries is an
Hello Hal -
I spent a lot of my RF engineering career in related areas, including radar,
EW, and spread spectrum timing
systems. Since the distance is short and the cost is an issue you may wish to
consider an analog
system solution.
Specifically your master station transmits a RF signal that
Joe wrote:
Back when I was in product engineering there was a VCO design that
used a superfilter circuit. It consisted of a pass transistor and
a filter cap from base to ground. The gain of the transistor
multiplied the effective capacitance. I have not seen this configuration since.
They
Hi
To complete the thought:
Three base stations on three different transmit frequencies over a 50 MHz
range. Mobile has a local oscillator at say 200 MHz. Filter the incoming
frequency range, stuff it into a mixer, filter the output. What's
transmitted back gets processed at the base station.
Sorry, Poul-Henning Kamp, I answered directly
to your mail address, I repost it here...
Il 2013-02-01 18:09 Poul-Henning Kamp ha scritto:
Content-Type: text/plain; charset=ISO-8859-1
In message 2bf4f4e8c8207ae0f94a7e1a1e63c...@quipo.it, Fabio Eboli
writes:
Il 2013-01-31 06:42 Mark
Well, I stand corrected. Weren't the TM 500 instruments marketed as low
cost?
Regards.
Max. K 4 O DS.
Email: m...@maxsmusicplace.com
Transistor site http://www.funwithtransistors.net
Vacuum tube site: http://www.funwithtubes.net
Woodworking site
This is a keeper. Note the strong peak at 60 Hz for the unfiltered
darlington.
Regards.
Max. K 4 O DS.
Email: m...@maxsmusicplace.com
Transistor site http://www.funwithtransistors.net
Vacuum tube site: http://www.funwithtubes.net
Woodworking site
Well the Tek current probe that goes in the power supply wasn't low cost. They
also had a nice bench supply that went in the box. But a lot of the instruments
weren't so fancy.
-Original Message-
From: Max Robinson m...@maxsmusicplace.com
Sender: time-nuts-boun...@febo.com
Date: Fri, 1
OK beer time came early eLORAN is off the air at 2000 UTC
On Fri, Feb 1, 2013 at 11:30 AM, paul swed paulsw...@gmail.com wrote:
By the way I am calling it eLORAN but I think UrsaNav has another name for
it.
Regards
Paul
On Fri, Feb 1, 2013 at 11:28 AM, paul swed paulsw...@gmail.com wrote:
38 matches
Mail list logo
