? Hello Dave
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? I'd be interested to know more about your disc dipole experiment, size and materials etc?
? A Google search brought up nothing.
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? 73s Tracey G5VU
?
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----- Original Message -----
Sent: 09/04/2025 22:28:49
Subject: Re: [tinysa] Wideband antenna
A better option to the discone is the bicone.? Sure, it's larger, but behaves a bit more like the LP over frequency, but without the directionality.? For his purpose, the discone may serve as the best choice.? I can't imagine what the Schwartzbeck costs.? It's a professional antenna widely used in EMC measurements for radiated emissions.?
If he really wants bandwidth, build a disc dipole.? I recently built an ugly version.? It measured well at or (mostly) under 2:1 from 135 MHz through 3 GHz and the pattern is dipolish.? Off hand I am not aware of anyone marketing such an antenna.? Someone should!
Dave - W?LEV
Dave - W?LEV
On Wed, Apr 9, 2025 at 01:09 PM, W0LEV wrote:
The Schwartzbeck log periodic is by far the better antenna.? I agree 100%, Dave.
At least if directionality is the goal.
Since the OP originally posted a vertical antenna, I presumed he wanted omni-directionality with flat gain over a large bandwidth.
And if that is the case, the discone is a better choice than his vertical or the log periodic antenna.
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A better option to the discone is the bicone.? Sure, it's larger, but behaves a bit more like the LP over frequency, but without the directionality.? For his purpose, the discone may serve as the best choice.? I can't imagine what the Schwartzbeck costs.? It's a professional antenna widely used in EMC measurements for radiated emissions.?
If he really wants bandwidth, build a disc dipole.? I recently built an ugly version.? It measured well at or (mostly) under 2:1 from 135 MHz through 3 GHz and the pattern is dipolish.? Off hand I am not aware of anyone marketing such an antenna.? Someone should!
Dave - W?LEV
Dave - W?LEV
On Wed, Apr 9, 2025 at 01:09 PM, W0LEV wrote:
The Schwartzbeck log periodic is by far the better antenna.?
I agree 100%, Dave.
At least if directionality is the goal.
Since the OP originally posted a vertical antenna, I presumed he wanted omni-directionality with flat gain over a large bandwidth.
And if that is the case, the discone is a better choice than his vertical or the log periodic antenna.
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On Wed, Apr 9, 2025 at 01:09 PM, W0LEV wrote:
The Schwartzbeck log periodic is by far the better antenna.?
I agree 100%, Dave.
At least if directionality is the goal.
Since the OP originally posted a vertical antenna, I presumed he wanted omni-directionality with flat gain over a large bandwidth.
And if that is the case, the discone is a better choice than his vertical or the log periodic antenna.
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Re: Determining antenna factor
I presume G is gain.? Is that in dB or the numerical ratio before the 10log[ratio]?
Dave - W?LEV
A handy formula…..plot your antenna gain vs. frequency and convert to AF vs. frequency
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-Charlie
?W5CDT
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The Schwartzbeck log periodic is by far the better antenna.? They offer a far flatter response response and are directional.? Directionality allows one to do a better job of finding RF emission locations.?
The gain plot for the "vertical" blob is over rated!!?
Discones can typically cover a 10-to-1 bandwidth while staying on or within the 2 : 1 circle on the Smith chart but are not directional and do not offer constand polarization with frequency.? Their only claim to fame is a 2 : 1 SWR over a 10-to-1 bandwidth.? They operate about like a 1/4-wavelength for the frequency of coverage.
Again the Schwartzbeck is by far the best choice.? I've used them professionally as do many accredited labs.??
Dave - W?LEV
I am asking first about the PCTEL OP451 antenna, but also in comparison with, say, a Schwarzbeck USLP 9143 Log Antenna ()
As I need the antenna as a mobile probe, which one/type is better to cover monitoring 900 MHz - 6/7 GHz spectrum with TinySA?
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In general, a log-periodic antenna will give flatter gain response over a wide frequency range than will a vertical antenna.
But the log-periodic antenna is more directional (in the direction of the 'arrow' of smaller radiators), so its forward gain will be different from signals off the side or back.
You should also consider a discone design, which is more omni-directional, but more even gain across the bandwidth.
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I am asking first about the PCTEL OP451 antenna, but also in comparison with, say, a Schwarzbeck USLP 9143 Log Antenna ()
As I need the antenna as a mobile probe, which one/type is better to cover monitoring 900 MHz - 6/7 GHz spectrum with TinySA?
?
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Re: Determining antenna factor
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Anybody used PCTEL OP451 (450 MHz – 6 GHz, VSWR <2.0:1, 50 Ohm) wideband antenna with TinySA Ultra?
It is a good match? Anybody had any experience with this one or a similar antenna? Pros and cons?
Should I be worried about cable length?
Specs seems to indicate that gain values include cable and connector losses.
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And reading the messages in group, I MUST use TRACE/CALC/TABLE TRACE and create a trace containing a 8 point linear interpolation of the AF versus frequency from the antenna gain graph?
Is it ok to "approximate" the graph points to only 8 points in the TABLE TRACE?
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Thank you!
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 ?
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Re: tinySA Ultra - signal generator specs
Well that wasn’t very smart! ?Yes, I’ve found the correct page now - thanks.?
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Re: tinySA Ultra - signal generator specs
You are reading the tinySA basic spec, try the tinySA Ultra spec
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Designer of the tinySA
For more info go to
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tinySA Ultra - signal generator specs
I'm trying to use the signal generator again, as I have many times.? But I'm looking for a bit more power than before.? I see that it is specified (at ) as -6 dBm in the "low" mode and +9 dBm in the "high" mode.? Yet the most I can get out of it is -17.9 dBm.? I must be missing something - what did I do?? This is the ZS405 version, I think.
Ron
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Did you read the change log?
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Designer of the tinySA
For more info go to
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I'll ask the question in a different way. There are versions in the tiny SA Ultra line (ZS-405, ZS-406, ZS-407) that probably differ in hardware. The latest versions of the software are mainly focused on the ZS-406,ZS-407 and are designed for this hardware (I may be mistaken). And now, if you use the latest software versions in the ZS-405, will this update have an improvement in performance? That's the question I'm interested in.I would like to hear the answer to my question from the creator of these devices.
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That's only with the FW release after the introduction of the Ultra+
If you run older FW there is no indication. Just tinySA Ultra, which means ZS405
--
Designer of the tinySA
For more info go to
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Hi?
in config, version, it is on the first line.....
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Re: TinySA Ultra operating temperature
These limits have indeed not been tested.
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Designer of the tinySA
For more info go to
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I agree with what has been said, done numerous updates no probs. Always do a self test prior to an upgrade, else if you have damaged the unit, you may think it was due to the upgrade
Generally as Clyde says make up your own mind.?
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Once you have done on a couple of updates there is no stress, providing care and basics are considered.?
Always fully investigate that others that have done it before you (excluding horror stories of incorrect process doers!) Dont be the guinea pig! If there are 100+ others with no reports of a show stopper, do it!?
Make sure its the right hardware and right software. This can take a bit of sorting out! Dont proceed until you are sure.??
Make sure all batteries are fully charged and never do it on batteries, always a solid UPS backed mains, where possible.?
Do two backups of all settings/configurations to external media or use a pen and paper/camera. Remove said media.
Read the process over and over, then read again and follow the process exactly. Every step. Create a checklist.?
Any major problem is likely going to be your fault!? Go over this list again.?
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Dont panic!?
Wait.?
Have coffee, dig the garden and then check it.??
Do a factory reset. You did backup all settings/configurations to external???
Restore settings.?
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If you have it all correct there are valid reasons for updating firmware as bug fixes, slight improvements, to major improvements. New features are few and far but even a little bug or label fix is worthwhile in my opinion.?
For example a NanoVNA 2020 to 2025, the difference was quite noticeable with the original level adjustments making no sense at all to me, and the update being common sense.?
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Since the dawn of the CPU I have done all manor of updates, consumer products, IT stuff inc motherboards, Cisco routers, $250K DTV 5KW transmitters, Marconi test gear, Agilent 3GHZ sig gen, encoders, decoders, associated link/studio equipment, Sony XD510etc cameras, minidisk recorders, with .00001 failure rate, by following basic rules.?
Maxwelloau VK5AC.
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Hi.
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If you connect the tinySA Ultra computer to the tinySA APP program, you will see this information in the log window.
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Generally as Clyde says make up your own mind.?
?
Once you have done on a couple of updates there is no stress, providing care and basics are considered.?
Always fully investigate that others that have done it before you (excluding horror stories of incorrect process doers!) Dont be the guinea pig! If there are 100+ others with no reports of a show stopper, do it!?
Make sure its the right hardware and right software. This can take a bit of sorting out! Dont proceed until you are sure.??
Make sure all batteries are fully charged and never do it on batteries, always a solid UPS backed mains, where possible.?
Do two backups of all settings/configurations to external media or use a pen and paper/camera. Remove said media.
Read the process over and over, then read again and follow the process exactly. Every step. Create a checklist.?
Any major problem is likely going to be your fault!? Go over this list again.?
?
Dont panic!?
Wait.?
Have coffee, dig the garden and then check it.??
Do a factory reset. You did backup all settings/configurations to external???
Restore settings.?
?
If you have it all correct there are valid reasons for updating firmware as bug fixes, slight improvements, to major improvements. New features are few and far but even a little bug or label fix is worthwhile in my opinion.?
For example a NanoVNA 2020 to 2025, the difference was quite noticeable with the original level adjustments making no sense at all to me, and the update being common sense.?
?
Since the dawn of the CPU I have done all manor of updates, consumer products, IT stuff inc motherboards, Cisco routers, $250K DTV 5KW transmitters, Marconi test gear, Agilent 3GHZ sig gen, encoders, decoders, associated link/studio equipment, Sony XD510etc cameras, minidisk recorders, with .00001 failure rate, by following basic rules.?
Maxwelloau VK5AC.
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R4ABT
Gerd
maxwelloau