Why? is it out of warranty ?
If still in warranty, they must accept returns
I think what Erik is suggesting is that it's failing the test because it's a clone,? so not much you can do to "fix" it
Cheers Dave VK2TDN
----- Original Message -----
To: <[email protected]>
Cc:
Sent: Fri, 21 Feb 2025 23:39:06 -0800
Subject: Re: [tinysa] Ultra failing tests
They don't want it back so I'd like to fix it if possible
Email sent using Optus Webmail
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They don't want it back so I'd like to fix it if possible
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Return to amazon
--
Designer of the tinySA
For more info go to
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Hello all,?
I ordered a NanoVNA but amazon sent me a SAUltra on accident (which I planned on ordering too anyways)
?
But it fails the self test and the calibration too. I fed in the 30MHz cal signal and it reads way low. My old SA reads the cal signal fine. When I connect an antenna, the FM broadcast band is faint to say the least. Any tips?
?
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Locked
Re: Attenuation for Ultra
When one KNOWS the source power AND the input level to the test instrument that will yield a faithful rendition of the input signal, one can EASILY determine how much attenuation is required.? PERIOD.?? P E R I O D......
If one can't handle powers of 10, logarithms, or adding and subtracting attenuator values, then one better go back and review one's very basic algebra.
PERIOD.....? P E R I O D....
Dave - W?LEV?
Dave - W?LEV
On Fri, Feb 21, 2025 at 03:02 AM, G8HUL wrote:
....but as has been stated here many times before damage level is far different form that which will give a realistic reading.
The 8568 is different from the TinySA in that its input attenuator is real resistors and can withstand 1W without damage, but there is still the necessity to ensure that sufficient attenuation is selected so that the SA is not overloaded and gives a sensible answer.
The wat to do that is to monitor both the fundamental and the harmonic and increase the attenuation level, and if the harmonic level (or fundamental) varies by more than the change in attenuation then you are not at a level that will give a true answer.
73
Jeff G8HUL
Thank you Jeff for this interlude of sanity.?? I was trained to start in a completely safe input level range, wide sweep, look for all the signals, calculate and note the safe maximum level (as Min attenuation) , THEN use the excellent HP attenuation range to sweep the on screen signal level up and down within that range until the fundamental and all harmonics of interest all moved in sync? which I think is what you are describing.? I can't remember this typically being the case at Max/damage input level or even near but who knows.?? Anyway? each to their own ...
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Locked
Re: Attenuation for Ultra
On Fri, Feb 21, 2025 at 03:02 AM, G8HUL wrote:
....but as has been stated here many times before damage level is far different form that which will give a realistic reading.
The 8568 is different from the TinySA in that its input attenuator is real resistors and can withstand 1W without damage, but there is still the necessity to ensure that sufficient attenuation is selected so that the SA is not overloaded and gives a sensible answer.
The wat to do that is to monitor both the fundamental and the harmonic and increase the attenuation level, and if the harmonic level (or fundamental) varies by more than the change in attenuation then you are not at a level that will give a true answer.
73
Jeff G8HUL
Thank you Jeff for this interlude of sanity.?? I was trained to start in a completely safe input level range, wide sweep, look for all the signals, calculate and note the safe maximum level (as Min attenuation) , THEN use the excellent HP attenuation range to sweep the on screen signal level up and down within that range until the fundamental and all harmonics of interest all moved in sync? which I think is what you are describing.? I can't remember this typically being the case at Max/damage input level or even near but who knows.?? Anyway? each to their own ...
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Re: Pre-sale, tinySA ULTRA plus
Contact Zeenko
--
Designer of the tinySA
For more info go to
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Re: Pre-sale, tinySA ULTRA plus
Eleshop no longer has the TinySa Ultra model (non-plus) in stock. From what the people there say, the old model, ZS-405, will no longer be produced and sold? For some reason, I would prefer to be able to buy the old model.
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Re: Looking for beta testers for a new product
Hello. I have GNSS (GPS and Galileo), frequency meter with a resolution of 0.0001 Hz, 150 MHz oscilloscope, a 4.4 GHz VNA, TinySa Ultra and other devices. If I can help in any way, I can help to the best of my ability. Thank you and congratulations on your projects.
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Locked
Re: Attenuation for Ultra
QUOTE: 5W minus 40dB sounds a bit too much input level for the HP.
40 dB down from 5 watts is 4 decades in power reduction. So: 5-W > 10 dB = 0.500 W.....0.500 -W
another 10 dB = 0.050-W.....0.050-W > another 10 dB = 0.005-W......0.005-W > another 10 dB
(for a total of 40 dB) = 0.0005-W or -3 dBm.
From the HP instruction book for the HP 8568, the maximum input power is +30 dBm or 1-watt.
Therefore, my input of 5-watts with a 40-dB pad, or -3 dBm (the first pad was a 50-watt 20 dB
attenuator followed by a 2-watt 20 dB attenuator) is well ..... WELL.... below the maximum input
power specified by HP.
You could have looked this up before you sent me the comment. I know what I'm doing, please
and thank you!!
....but as has been stated here many times before damage level is far different form that which will give a realistic reading. The 8568 is different from the TinySA in that its input attenuator is real resistors and can withstand 1W without damage, but there is still the necessity to ensure that sufficient attenuation is selected so that the SA is not overloaded and gives a sensible answer. The wat to do that is to monitor both the fundamental and the harmonic and increase the attenuation level, and if the harmonic level (or fundamental) varies by more than the change in attenuation then you are not at a level that will give a true answer. 73 Jeff G8HUL
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Locked
Re: Attenuation for Ultra
I always try to keep the signal around -30dBm so that spurs aren't a problem. The HP does have a full step attenuator so the OP's posted levels would work for HP but would be a problem for the TinySA in terms of that.
A full 0 to 60dB step attenuator would be a nice thing for the TinySA but one that is good to the entire frequency range costs many times what the TinySA costs! Most of the time you can get by with a sampler in combination with an external attenuator?or two.
73, Staff Scientist Andritz Rolls Global Research Center (RETIRED)
On Thu, Feb 20, 2025 at 4:29?PM Andy G0FTD via <punkbiscuit= [email protected]> wrote: On Thu, Feb 20, 2025 at 04:40 PM, Bruce Akhurst wrote:
5W minus 40dB sounds a bit too much input level for the HP.? ?Not at damage level by any means but above the requirement for a clean result on harmonics etc . .? ? ISTR -30dBm being the typical sweet spot . .?
I think you may be getting a little confused with figure and different spectrum analyzer
specs.
?
The Tiny SA stuff is VERY sensitive, and requires a good deal more attenuation.
The -30dbm figure is probably is more like the figure that's good for the max level of a
Tiny SA in order to have both a decent dynamic range and not to produce any
of it's own potential unwanted / misleading internal products.
?
I think my old HP8594E could handle 1 watt at the input +30dbm ?
?
Hint - Dave is ex HP, so should know what his ex emplyers products can
handle ;-)
?
73 de Andy
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Locked
Re: Attenuation for Ultra
On Thu, Feb 20, 2025 at 04:40 PM, Bruce Akhurst wrote:
5W minus 40dB sounds a bit too much input level for the HP.? ?Not at damage level by any means but above the requirement for a clean result on harmonics etc . .? ? ISTR -30dBm being the typical sweet spot . .?
I think you may be getting a little confused with figure and different spectrum analyzer
specs.
?
The Tiny SA stuff is VERY sensitive, and requires a good deal more attenuation.
The -30dbm figure is probably is more like the figure that's good for the max level of a
Tiny SA in order to have both a decent dynamic range and not to produce any
of it's own potential unwanted / misleading internal products.
?
I think my old HP8594E could handle 1 watt at the input +30dbm ?
?
Hint - Dave is ex HP, so should know what his ex emplyers products can
handle ;-)
?
73 de Andy
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Locked
Re: Attenuation for Ultra
QUOTE:?
5W minus 40dB sounds a bit too much input level for the HP.?
40 dB down from 5 watts is 4 decades in power reduction.? So:? 5-W > 10 dB = 0.500 W.....0.500 -W > another 10 dB = 0.050-W.....0.050-W > another 10 dB = 0.005-W......0.005-W > another 10 dB (for a total of 40 dB) = 0.0005-W or -3 dBm.??
From the HP instruction book for the HP 8568, the maximum input power is?+30 dBm or 1-watt.? Therefore, my input of 5-watts with a 40-dB pad, or -3 dBm (the first pad was a 50-watt 20 dB attenuator followed by a 2-watt 20 dB attenuator) is well ..... WELL.... below the maximum input power specified by HP.???
You could have looked this up before you sent me the comment.? I know what I'm doing, please and thank you!!
Dave - W?LEV
5W minus 40dB sounds a bit too much input level for the HP.? ?Not at damage level by any means but above the requirement for a clean result on harmonics etc . .? ? ISTR -30dBm being the typical sweet spot . .?
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SVHFS Conference 2025, Call for Papers & Presentations
Here's an update on the SVHFS 2025 Conference;? Deadline for papers has been extended to March 17 Conference & hotel registration is open; details are in the attached file.
Thanks,
Robin Midgett K4IDC
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Looking for beta testers for a new product
For a new product I'm looking for a number of testers, preferably in Europe
The product is tiny and has a high resolution dual time stamping and frequency/phase measurement capability
Frequency/time/phase reference can be external or internal using a built in gpsdo.
The accuracy is less then the tinyPFA but it has much more functionality
No specific test equipment availability is required but it's important to have a project that can benefit from the above functionality to ensure actual usage.?
If you are motivated to join the testing and do have sufficient time to frequently load, test and report on firmware updates, please send me a private reply with some info on your project and how you intend to use the product.
If available, you can add some info on your experience and relevant test equipment
Replies to the list will be ignored.
?
--
Designer of the tinySA
For more info go to
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Locked
Re: Attenuation for Ultra
5W minus 40dB sounds a bit too much input level for the HP.? ?Not at damage level by any means but above the requirement for a clean result on harmonics etc . .? ? ISTR -30dBm being the typical sweet spot . .?
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Re: dfu-util warnings and errors (ZS405 and ZS407)
It was just a solution to suppress the initial error message during flushing. I am not sure yet why this message was showing in the first place. Maybe not a problem or an indicator of some hidden problems. Not sure yet.
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Re: What to do when a selftest fails
Herb thanks for the advice. I'm ordering spares and will replace the switch first
Bob E - thanks I'll be getting a DC block for sure
Erik thanks I'll will be using a attenuator and DC block from now on. Many thanks for making this wonderful
?? test equipment available
Bob G I was using it as a signal generator at the time. I did exactly that, connected directly to scope and then
?? attached the 50ohm terminator to check the level. Thanks for your input
Regards, Reggie
?
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Re: What to do when a selftest fails
The input capacitor is around 1uF SMT. Hard to get these in high voltage.
Mind you, I would like to see a slightly higher voltage cap used. But I believe the main problem is the breakdown voltage of the protection diodes.
Erik may like to comment.
Regards...Bob VK2ZRE
toggle quoted message
Show quoted text
On 20/02/2025 3:10 am, Terry Perdue via groups.io wrote: ? That is why a DC Block is such an important part of your test kit. It is just a capacitor in series with the centre conductor in an SMA-M to SMA-F adaptor.
Make sure it has a DC rating of at least 100V, preferably 200V. Many of the units on Ebay, etc are only rated at ~20V DC isolation.
HTH Someone...Bob VK2ZRE With a higher voltage coupling cap, isn¡¯t damage still likely due to the voltage spike as it is connected to a >5V source? I¡¯m sure Erik would have used a higher voltage cap if that weren¡¯t the case.
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Re: What to do when a selftest fails
No DC on the input to the counter.? Not sure about input cap, I replaced the AS179-92 LF? and didn't go any further. It worked after switch replacement.
On Wed, Feb 19, 2025 at 2:14 PM, Terry Perdue via groups.io <K8tp@...> wrote: Does the counter show any DC on its input, and is the tinySA¡¯s input cap now shorted?
>? I had mine at what I think is maximum output (-18 dbm) for 45 minutes feeding my scope without a probe and then I tee'd in a 50 ohm input frequency counter and that killed the AS179-92LF input switch. It took a few seconds, I was watching the scope and the signal decayed within 5 seconds of hooking up the counter.
> Bob
>
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Dave
Bruce Akhurst
George - YO9HSW
JCR
Sam Reaves
Robin Midgett
Rob, W9LOT