Re: U22 AS179-92LF replacement
Thanks.? I ask the question as it says "20 Mhz to 3 Ghz " on the data sheet, and most of my work is in the HF bands ( 1.8 Mhz to 30 Mhz ) and the TinySA Ultra itself says " 100Khz to 6Ghz "? I just wanted to make sure this is the right component.
Thanks again.
Dave.
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Re: U22 AS179-92LF replacement
Seems OK
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Designer of the tinySA
For more info go to
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U22 AS179-92LF replacement
Hi, my TinySA Ultra is showing all the symptoms of a failed U22. Self inflicted I think so can’t blame the unit.
I’ve ordered a new unit as the supplier I bought it from has offered me a discount.
So as I’ll have nothing to loose I thought I’d have a go at replacing it. I’ve got a hot air soldering unit so lets see.
My question is the description on my preferred suppliers ( CPC ) for a AS179-92LF is “?
Switch IC, SPDT, 20MHz to 3GHz, 2V to 5V, SC-70-6?-?
AS179-92LF “?
Could someone please confirm this is what I require.
Many thanks and apologies for the capitals it’s a result of copy/paste.
Dave
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True that. If I had my way it would be a world-wide law that every battery powered portable device has to have a hard OFF switch. However there is also the protection board attached to the cells that is in play, plus any circuit leakages around that switch for whatever reason. The charging electronics in particular do not disconnect with the power switch. As I wrote, very small but non-zero. At any rate, as a case in point I once let my early NanoVNA-H languish for some months. It also has a physical switch but still the battery suffered. It was damaged somewhat but not completely ruined so I was able to use the unit for some time before I replaced the battery. Now I periodically check its charge if I have not used it in a while and maintenance charge if necessary. Better safe than sorry. You should see the battery I just replaced in my portable HDTV that has been not been used in several years. It too has a physical switch. The battery was puffed up to the point where it would have made a decent pillow for a small creature. It is fortunate that the battery cover returned to its former shape (and that the battery did not rupture). On Sun, 06 Apr 2025 08:07:22 -0700 "Gerd via groups.io" <gerd.vipre@...> wrote:
Sometimes I wonder how many long forgotten iPods have been found in desk drawers with dead and swollen batteries. The TinySA model has a physical switch that disconnects the battery from the power circuit. The iPod and newer devices are built on a digital switch that constantly draws some current.
-- 73 -Jim NU0C
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> Sometimes I wonder how many long forgotten iPods have been found in desk drawers with dead and swollen batteries.
The TinySA model has a physical switch that disconnects the battery from the power circuit. The iPod and newer devices are built on a digital switch that constantly draws some current.
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While the long shelf life is true, it is also true that in the real world there is often a very small but non-zero current drain on the cells. Sometimes I wonder how many long forgotten iPods have been found in desk drawers with dead and swollen batteries. For this reason it is wise to pull the unit out of storage periodically to check the state of charge and maintenance charge it if necessary. On Sun, 06 Apr 2025 06:32:41 -0700 "DAVE REISER WA3TRS via groups.io" <DAVEREISER@...> wrote: Thank you for the information.? When setting the tinySA aside, one does not consider such a thing.? ?I will now.
73s, -- 73 -Jim NU0C
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Re: TinySA Ultra operating temperature
The internal reference should be stable enough for the resolution of the tinySA
Should be well within one 1 Hz stability.
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Designer of the tinySA
For more info go to
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Thank you for the information.? When setting the tinySA aside, one does not consider such a thing.? ?I will now.
73s,
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Re: TinySA Ultra operating temperature
Hi.
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Erik - Has it been tested at what environmental temperatures the parameters of the pilot signals measured will start to shift?
(For example, if you put the tinySA ULTRA in a closed device box and put it in the attic of a house to collect data for a certain period of time)?
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Sincerely,
g.
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Re: TinySA Ultra operating temperature
No formally specified minimum or maximum operating temperature
What temperature are you thinking about?
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Designer of the tinySA
For more info go to
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If you just want to measure the loss at a few frequencies, then you could measure the output of an oscillator direct then connect the SA and re-measure. Don't overload the input. Not as good as a VNA which will give a lot more information.
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TinySA Ultra operating temperature
Is there any specified operating temperature range for the TinySA ultra device?? ?I cannot seem to find this on the wiki or searching group messages.??
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Cheers,
TC
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Re: TinySA ULTRA 4" - No longer works
Hi.
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> if you have a look to the copper pattern of the ribbon cable you can see that it is not centered
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Yes, it caught my eye right away.
I enlarged the picture I took earlier.
 
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Re: TinySA ULTRA 4" - No longer works
Hi.
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Erik, thanks for the reply.
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For a few hours tinySA ULTRA was turned off and when I restarted it, this information appeared on the screen (Pictures attached to the letter).
The only way to get out of this state was to do a "hard restart" // push the jog button to the side (NOT down) WHILE RESTARTING the device //.
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Is this a pure software problem and not indicative of a hardware defect ?
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At that moment TinySA ULTRA has on it that software: "tinySA4_v1.4-109-g5cfd570"
I installed the latest software on the device "tinySA4_v1.4-199-gde12ba2" and will see if this type of anomaly occurs again.
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Sincerely,
g
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Re: TinySA ULTRA 4" - No longer works
(sorry for my reply in bold letters)
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Re: TinySA ULTRA 4" - No longer works
if you have a look to the copper pattern of the ribbon cable you can see that it is not centered - you can also see that the size of the isolation area at the edges is different -? and also on the imprints of the connector.. a bad fabricated ribbon cable..
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Lithium Ion batteries have almost zero self discharge. So providing there is no current draw they should remain charged anlmost indefinitely.
Having said that, it’s kinder to the battery to not store it fully charged. For long term storage around 50% SOC is much kinder to the longevity of the battery. Peter.
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Hooray for the tinyVA battery.? I had not used my unit in over a year, turned it on, and the battery was at almost full charge.? To me, that is an outstanding shelf life from a quality rechargeable battery.? Thank you.
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Re: Measuring resonant coil outputs
Hi Dave,
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Lots of useful info there. Thanks. I will also write separately to you.
--
Julian
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Re: TinySA ULTRA 4" - No longer works
On Fri, Apr 4, 2025 at 04:32 PM, Gerd wrote:
Erik, did you design the printed circuit board ?
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Yes
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Before I started to disassemble the device, I decided to check if the signal generator was working. A picture of this menu is attached to the letter, the problem also affected this part of the control circuit. When I selected LOW OUTPUT - ON from the menu, a signal appeared at the RF tinySAoutput, but the frequency barely ran 50MHz. From that frequency onwards, the device could no longer hold the signal carrier. I have not tested the signal generator of this device before, so I have no comparison of how it should work.
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You have to switch the signal generator LOW OUTPUT to ON to get the correct output signal
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I opened the tinySA ULTRA at Erik's suggestion and a visual test did not detect any poor connections.
Since I have had problems with similar cable connections in other devices before, I cleaned the cable terminals just in case (even though there was no visible problem).
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After reconnecting the ribbon cable, almost all problems disappeared. Self Test was successful.
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Happy to hear
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Even after a successful Self Test, the signal generator is unable to transmit a signal in normal mode, I have to activate LOW OUTPUT - ON in the menu. Is this a normal approach or is there another problem here?
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This is normal behavior
I also took a picture of the last measurement.
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Erik, based on the information you provided, could you tell me which terminal in the ribbon cable had a poor connection? I'll look at it later with a powerful microscope. (It seems that some types of connectors are not worth the money.)
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Don't know, sometimes we see this problem, hence the suggestion to reseat the cable.
--
Designer of the tinySA
For more info go to
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Combemartian
Jim Shorney
Gerd
DAVE REISER WA3TRS
Kerrowman