Re: Attenuator Recommendations
Pasternack is not (in my opinion) an
inexpensive distributor.
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Paul, W8AEF
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From: [email protected] [mailto:[email protected]]
On Behalf Of Matthew Rapaport
Sent: Saturday, October 21, 2023
2:39 PM
To: [email protected]
Subject: Re: [tinysa] Attenuator
Recommendations
?
That can handle 100 watts??? Don't know about making your own... The
50db 100 watt pictured at the link is $1000.00 U.S! The 40db is $900.00! Not
cheap!!?
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Re: Attenuator Recommendations
There is a Chinese company that sells on Amazon.
Look for Becen, that is their name.
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Re: Attenuator Recommendations
The one I have is rated at 100 watts. I got it from M3 Electronix
which has been gone for years. I did find the instructions for the
kit.
Jim - W4BQP since 1953
On 10/21/2023 5:39 PM, Matthew Rapaport
wrote:
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That can handle 100 watts??? Don't know about
making your own... The 50db 100 watt pictured at the link is
$1000.00 U.S! The 40db is $900.00! Not cheap!!?
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Re: Attenuator Recommendations
Suggestion for a 100-watt transmitter:
1)? start with a 6 dB attenuator at 100-watts.? You're now down to 25-watts.
2)? follow that with another 6 dB attenuator at 10-watts.? You're now down to 6.25-watts.
3)? follow that with a 10 dB attenuator at 5-watts.? You're now down to 0.625-watts or -2 dBw or +28 dBm.
From there on down, a good switchable 2-watt attenuator to -100 dB attenuation will handle about anything.
In the future, you'll find many, m a n y? uses for your investment.
Dave ?
On Sat, Oct 21, 2023 at 8:50?PM Jim Campbell < jecspasc@...> wrote:
40 db resistive taps are not all that expensive and there are plans
on the internet to build your own.
Jim - W4BQP since 1953
On 10/21/2023 4:24 PM, Matthew Rapaport
wrote:
I was going to say if you're going to put out 100
watts that first attenuator on the radio is not going to be
cheap.. probably a variable attenuator of some?sort with a
substantial built-in dummy load... Disapating 100 watts is not
trivial..
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Re: Attenuator Recommendations
That can handle 100 watts??? Don't know about making your own... The 50db 100 watt pictured at the link is $1000.00 U.S! The 40db is $900.00! Not cheap!!?
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Locked
Re: Windows 11 does not properly load tinySA in DFU mode.
I updated the firmware of my TinySA Ultra on Linux/Ubuntu with the 'dfu-util' command, as advised at
(you may have to install dfu-util first)
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Re: Attenuator Recommendations
40 db resistive taps are not all that expensive and there are plans
on the internet to build your own.
Jim - W4BQP since 1953
On 10/21/2023 4:24 PM, Matthew Rapaport
wrote:
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I was going to say if you're going to put out 100
watts that first attenuator on the radio is not going to be
cheap.. probably a variable attenuator of some?sort with a
substantial built-in dummy load... Disapating 100 watts is not
trivial..
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Re: Attenuator Recommendations
Right..
100 Watt incandescent bulbs are getting harder to find. (evil grin).
73,
Bill ?KU8H
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On Oct 21, 2023, at 4:24 PM, Matthew Rapaport <quineatal@...> wrote:
? I was going to say if you're going to put out 100 watts that first attenuator on the radio is not going to be cheap.. probably a variable attenuator of some?sort with a substantial built-in dummy load... Disapating 100 watts is not trivial..
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Re: Attenuator Recommendations
I was going to say if you're going to put out 100 watts that first attenuator on the radio is not going to be cheap.. probably a variable attenuator of some?sort with a substantial built-in dummy load... Disapating 100 watts is not trivial..
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Re: Attenuator Recommendations
IF you want to measure higher power from a transmitter, a nice 40db tap works great, eary to homebrew, do a duck duck and a couple of "how to" show up,? Gets the power down where you can use the 1w and smaller rated attenuators...
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Re: Attenuator Recommendations
I had that one too, but the switches crapped out on me,? I tried Deox, and all manner of cleaners, I guess just cheap switches...? I scored some mini-circuits stick attenuators at Dayton one year, they had a booth at the time, and had a bunch on clearance at about 1/4 the list price...? ?Found an old HP 355D 10db stepper at another, and also a Kay-837, seems to work pretty good.? I see that ebay has some 355D for about $100, only good to a gig though...? ?Ebay is a gold mine for attenuators, just have to be careful they are not burnt...?
Best of Luck
Regards
wb7ond
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Locked
Re: Windows 11 does not properly load tinySA in DFU mode.
It works fine on both of my Windows 11 systems, but they are both running the Canary preview version, so that may have an effect.
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Locked
Re: Windows 11 does not properly load tinySA in DFU mode.
Well I think Windows?11 appears to be the problem. I have Windows?10 Pro ver. 22H2 (19045.2006) and have no problems even with USB3.
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Re: Attenuator Recommendations
I have only HTs to test and transmit 1 watt. 60db of attenuation is perfect--results in 1 millionth of a watt going into the tinysa. 30db is on the radio (10 watt capacity so HT output is 1 thousandth of a watt) and another 30db (2 watt capacity) on the tinysa port. See pictures). If you're transmitting 100 watts you're going to need 80db attenuation to get the same 1 millionth of a watt. I would put 50 on the radio and then you can use the 30db on the port..?
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Locked
Re: Windows 11 does not properly load tinySA in DFU mode.
Some extra information on the troubleshooting I've done up to now.
I have:
- Uninstalled the device from device manager.
- Removed all extra USB devices
- Turned off Memory Integrity
- Searched for suitable drivers from the device's properties window.
- power cycled both the laptop and the tinysa multiple times.
- used different cables
- bought a USB 2 hub to connect the tinysa
- used different usb ports for the hub and the tinysa cable
- used both the tinysa-app and the STCUBEPROGRAMMER
I'm not sure what else to do at this point.
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Locked
Re: Windows 11 does not properly load tinySA in DFU mode.
So I've plugged in the USB 2.0 hub and nothing has changed. I have removed all devices aside from the new hub and the SA.
Even weirder is this:
There are no other entries for the SA in the device manager.
The tinySA-App reports this when trying to connect to the DFU.
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Loading "C:\Users\jpiro\Downloads\Electronics Projects\Tinysa\tinySA_v1.4-120-g6c349b9.dfu" ..
112829 bytes loaded OK from C:\Users\jpiro\Downloads\Electronics Projects\Tinysa\tinySA_v1.4-120-g6c349b9.dfu
DFU element address [0]: 0x08000000
DFU element size [0]:? ? 112520
Firmware size: 112520 bytes
Opening \\?\usb#vid_0483&pid_df11#fffffffeffff#{a5dcbf10-6530-11d2-901f-00c04fb951ed}?
?open failed?
No valid DFU device found
Have you put your NanoVNA into DFU mode ?
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Re: Attenuator Recommendations
I have a lot of small SMA attenuators I've purchased on eBay. The small ones are rated at 2 watts. I have some 1, 2, 3, 4, 5, 10, 15, 20, 30 dB attenuators. I have a few 20 dB 5 watt attenuators. I have one 30 dB 50 watt attenuator with N connectors.
Zack W9SZ
On Sat, Oct 21, 2023, 2:16 AM John K7ESQ < k7esq@...> wrote: Hello All,
What would be a good range of power attenuators (both watt rating and dB) to have on hand for use with the Ultra, primarily for ham radio use with 100-Watt transceivers, 50-Watt mobile transceivers, and 5-Watt HTs (checking harmonics, power output, etc.)? Thanks in advance.
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Re: Attenuator Recommendations
Hello John,
I use a 50dB tap and a 90dB step attenuator for my measurements.??
The step attenuator I have is this one:
The following is a similar step attenuator with a 30dB maximum that could work with the tap.
I found the best results for the tap from a pdf online.? The two that I purchased had worse metrics tested with a NanoVNA.? I did have to adjust the capacitor to get a flatter response across a 0 to 150MHz span.
Other builds have been reported to work as well or better.? Some use a wire next to the tap resistors to adjust the capacitance value.
Note that you need a dummy load rated for the transmitter's power output with the tap.? You must verify that the dummy load is accurate over the frequency range you want to measure.
Most of my measurements are less than 25 watts, so I have purchased a 25-watt 50dB 0 to 3GHz fixed attenuator:
This allowed me to measure higher frequencies and overcome some of the limitations of my MFJ dummy load.
Above are my experiences.? Others may have different experiences and come to different results.? As for any advice from the internet, I suggest you research, learn, and develop your conclusions.
73
Evan
AC9TU
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Attenuator Recommendations
Hello All,
What would be a good range of power attenuators (both watt rating and dB) to have on hand for use with the Ultra, primarily for ham radio use with 100-Watt transceivers, 50-Watt mobile transceivers, and 5-Watt HTs (checking harmonics, power output, etc.)? Thanks in advance.
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Re: Detecting low power motion sensors
The Ultra will definitely work up and past
10.535GHz as seen in pics below.
Mike C. Sand Mtn GA
On 10/20/2023 8:51 AM, Martin via
groups.io wrote:
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On Sat, Oct 14, 2023 at 04:50 PM, ANDREAS Decker wrote:
frequency span 100 MHz, Min Hold, RBW 300 KHz, LNA=ON.
Use a narrower sweep bandwidth, wider RBW and Max hold.
<6GHz the LNA is fine, it gradually gets worse as you go higher
in frequency, but you should still be able to see older 10GHz CW
doppler radars without too much difficulty, although they are not
that stable.
Regards,
Martin
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Ion Petroianu
Jim Myers
Dentron
John K7ESQ
Mike C.