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I have FDX and HDX animal tags working at 134kHz.
If I do a 'lf seach', only the FDX tags are identified. For the HDX tag, no tag is detected.
If I do a 'lf read' the FDX data is read, but if I do it with the HDX tag, the data in the plot window shows only noise. The max = 0, min = -5 and mean = -2...
What could I do to read the HDX tags?
Thanks!
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set
lf config Hdo
lf read
data save xxx.pm3post the .pm3 file on a fileshare and link it here.
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i assume the tag is very small? if the above doesn't get something we can work with you may need a small focused antenna.
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Hi marshmellow
Thanks for your reply!
Here is a link to both the FDX and HDX data: The FDX works fine, but the HDX does not.
In the plot view, nothing(only noise) is seen, where the FDX you can see the waveforms.
I have a couple of tags, and none of the HDX tags work. They were read by a commercial reader, I tested them to make sure they work.
They are 30mm in diameter, standard animal tags.
https://www.dropbox.com/sh/zv20kwfrkl0kyrg/AABWHXAc9R1Jm3pS5Z6TEfUVa?dl=0
Thanks!
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are you sure they are 134khz? and you configured the pm3 for 134khz?
what is your antenna voltage without a tag, and with a tag?
what is your antenna size (or diameter)?
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Yes, they are 134kHz tags, we tested them with a commercial reader, and they worked.
It's standard off the shelf 30mm HDX tags.
Antenna voltages, no tag present:
Measuring antenna characteristics, please wait...
# LF antenna: 15.40 V @ 125.00 kHz
# LF antenna: 26.95 V @ 134.00 kHz
# LF optimal: 30.25 V @ 131.87 kHz
# HF antenna: 0.89 V @ 13.56 MHz
# Your HF antenna is unusable.
Displaying LF tuning graph. Divisor 89 is 134khz, 95 is 125khz.
Antenna voltages, with tag lying on antenna:
Measuring antenna characteristics, please wait...
# LF antenna: 12.65 V @ 125.00 kHz
# LF antenna: 25.02 V @ 134.00 kHz
# LF optimal: 25.02 V @ 133.33 kHz
# HF antenna: 0.89 V @ 13.56 MHz
# Your HF antenna is unusable.
Displaying LF tuning graph. Divisor 89 is 134khz, 95 is 125khz.
Here is example of me doing a lf search:
proxmark3> lf config H
#db# LF Sampling config:
#db# [q] divisor: 88
#db# (b) bps: 8
#db# [d] decimation: 1
#db# [a] averaging: 1
#db# [t] trigger threshold: 0
proxmark3> lf search
NOTE: some demods output possible binary
if it finds something that looks like a tag
False Positives ARE possible
Checking for known tags:
Waiting for a response from the proxmark...
Don't forget to cancel its operation first by pressing on the button
Command timed out
The plot window then opens, and the max=-1, min=-5 and mean=-2. Thus it seems no voltage is applied to the antenna?
I also have FDX tags from the same supplier, they work as expected.
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Try
lf read
data plot
Does it look any different.
lf search will never find it as it isn't a known tag
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You haven't said the size of your antenna. With small tags sometimes small focused antennas are required.
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The size of the antenna is 30mm for the tag, and the standard LF antenna as supplied by Rysc Corp.
I'm using these tags:
http://www.rfid-experts.co.za/#Product-Tags
'lf search' finds the FDX tags, but not the HDX tags...
'lf read'
'data plot' gives no results. its a flat line, max=-1,min=-5 and mean=-2. So it seems the A/D gets no voltage input from the antenna.
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I would guess your antenna is not focused enough or not quite strong enough to power the HDx tag. Maybe both
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So why are the FDX tags working?
And I'm using the Rysc PM3 antenna.
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Yes, I don't particularly like the rysc PCB antenna, I would avoid it for small tags.
Don't get me wrong, it is a pretty good all around antenna, but not great.
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