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Hello,
? Beside getting a SWR meter is there a different way to measure the actual power from the ft817? ?Could I use a multimeter?
regard,
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A swr meter aint gonna give you a power reading is it, its gonna give you a swr reading, unless you get something like a cross needle power/swr meter or the like, as for the mulitmeter, err i dont think so.
Mick SA4MDN
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Measure the peak-to-peak voltage across a dummy load with an oscilloscope.
--
Mike G8GYW
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And don't forget to check the rf output on the 6 bands mentioned in the service manual in case a golden screwdriver has been in the alignment menus, there are 24 outputs in total that can be altered.
Andy
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The best way is with an accurate wattmeter. I have a Bird 43 with an assortment of slugs, including 5 and 10 watt slugs for HF, VHF and UHF bands.
Zack W9SZ
Hello,
? Beside getting a SWR meter is there a different way to measure the actual power from the ft817?? Could I use a multimeter?
regard,
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And with a good dummy load. ? Or use a terminating wattmeter such as the Bird 6104 Which has scales down to 2W FSD. ? 73….Eric VK2VE. ?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]> On Behalf Of Zack Widup
Sent: Wednesday, June 26, 2024 1:55 AM
To: [email protected]
Subject: Re: [ft817] Measuring the output power? The best way is with an accurate wattmeter. I have a Bird 43 with an assortment of slugs, including 5 and 10 watt slugs for HF, VHF and UHF bands. ? Hello,
? Beside getting a SWR meter is there a different way to measure the actual power from the ft817?? Could I use a multimeter?
regard,
|
Multimeters rarely will measure above a couple of hundred Hz.? You could use an RF probe and a dummy load.? I bought a Surecom power meter on Amazon a few months back for UHF and VHF.? They also make one for HF at about $65 on Amazon. ?
You will still need a dummy load.
--
Al Skierkiewicz
WB9UVJ
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You can build a simple RF probe but you need to calibrate it. ?A simple SWR meter does not measure power over a wide range of frequencies. ?If possible, borrow a Bird 43 wattmeter from a local ham.
You can use that device to calibrate the power of your measurement equipment.
Check out kc9om.com. ?He sells some great kits and gives excellent service.
You can also build own watt meter using a Arduino UNO, a power tap and dummy load
See my rather crude video that I produced 4 years ago to see a demo of a talking watt meter.
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Bernard,
The website you provided does not work. Could it be a typo? The call is not good on QRZ.? Maybe the website is no longer around?
Fred/N7PN
On Tue, Jun 25, 2024 at 1:31?PM Ham Radio via <bernard.murphy= [email protected]> wrote: [Edited Message Follows]
You can build a simple RF probe but you need to calibrate it.? A simple SWR meter does not measure power over a wide range of frequencies.? If possible, borrow a Bird 43 wattmeter from a local ham.
You can use that device to calibrate the power of your measurement equipment.
Check out .? He sells some great kits and gives excellent service.
You can also build own watt meter using a Arduino UNO, a power tap and dummy load
See my rather crude video that I produced 4 years ago to see a demo of a talking watt meter.
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No multimeters do not measure power.? Nor will they respond to voltage at frequencies? the FT818 will work at.
IMHO all Ham should have a SWR meter and one that is calibrated for power.? It can be useful in many ways, just not monitoring the rig's output, but also aiding in making antennas.
If getting a power meter make sure it is made for the frequency you need.
73, ron, n9ee/r Ron Wright, N9EE/R Hernando Co ARES EC
Spring Hill, Florida also n9ee55@...
On Tuesday, June 25, 2024 at 04:05:29 PM EDT, Ham Radio <bernard.murphy@...> wrote:
An RF probe is easy to make but should be calibrated. ?A plain SWR meter does not measure power across a large frequency range. ?Borrow a Bird 43 from a local ham and calibrate your device(s) including a SWR bridge, ?if you have one.
You can also make a watt meter using a Arduino Uno and with a power tap and a dummy load. ?I have built one that speaks and one that generates CW. ?Click on link below for details.
https://youtu.be/RbaCiTmmYDQ?si=1N9Oz01RQD_J1DJ6
Also, check out KC9ON.COM. ? ? ? He sells some very nice kits and is really nice person to deal with.
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Fred.
Can you ?try the link ?again?
I deleted the original post because I did not hyperlink the URL. Send me a DM if you still have an issue as the reposted message does work for me.
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To the original poster (on3plz ?):
I've been following this thread, and
maybe I've missed something, but I have a question that I don't
see any answers to-? particularly since this is a ft817 group- why
do you feel a need to measure power?? I presume it's a measurement
at maximum level of 5 watts, or perhaps a bit more- but knowing
why you desire to make measurement(s) helps with answering the
question:
(a) if you're looking to make some
adjustments to "peak" a power output adjustment, it's probably not
necessary to accurately measure the actual power level- a simple
analog meter (VTVM, or VOM) connected to a signal (or germanium)
diode detector that's measuring the voltage across a 47, 50, or 51
ohm non-inductive resistor might be sufficient as it provides a
relative measurement, where small changes can be easily observed
but
(b) if you're looking to increase the
ft817 power output above 5 watts- I've been told that it can be
done- but I suspect that you will be stressing the radio
and
(c) if you're looking to get accurate
measurements of power output (to several decimal places) keep in
mind that such accuracy is difficult to provide without calibrated
instruments and reference elements (for example- dummy load
characteristics).
Mike N4MWP
On 6/25/24 16:31, Ham Radio wrote:
toggle quoted message
Show quoted text
[Edited Message Follows]
You can build a simple RF probe but you need to calibrate it.
?A simple SWR meter does not measure power over a wide range of
frequencies. ?If possible, borrow a Bird 43 wattmeter from a
local ham.
You can use that device to calibrate the power of your
measurement equipment.
Check out kc9om.com. ?He sells some great kits and gives
excellent service.
You can also build own watt meter using a Arduino UNO, a power
tap and dummy load
See my rather crude video that I produced 4 years ago to see a
demo of a talking watt meter.
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I designed a QRP SWR and power meter:
https://g8gyw.github.io/
--
Mike G8GYW
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Bernard,
The link works now. Maybe the site was down when I tried it.
Thank you for reaching out!
Fred/N7PN
On Tue, Jun 25, 2024 at 3:02?PM Ham Radio via <bernard.murphy= [email protected]> wrote: Fred.
Can you ?try the link ?again?
I deleted the original post because I did not hyperlink the URL. Send me a DM if you still have an issue as the reposted message does work for me.
-- Fred Hules II (602) 717-0345
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On 2024.06.25 06:37, Michael Newbury wrote: A swr meter aint gonna give you a power reading is it, its gonna give
you a swr reading, unless you get something like a cross needle
power/swr meter or the like, as for the mulitmeter, err i dont think
so.
Mick SA4MDN Hi Mick, Three of my bridges do. 73, John -- John D Erskine VE7MHI VA7OTC CN88hk VA7RCN Victoria, B.C.
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I had forgotten that QRPGuys makes a nice little power meter accessory. ? for $40.? It was very easy to put together and includes a QRP dummy load on the board.? I think I built it in one night.? I have it sitting on a shelf under my station monitor.? It is battery operated so I only connect it when I need to verify power and my other meters.? It is a very handy device.? You need to wind the transformer but that is the hardest part of the kit.? It is very small and there is a 3D printed box that you can make too.? They use PayPal as an interface for payment and shipping.? Please see their for details.
--
Al Skierkiewicz
WB9UVJ
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This looks like a nice product! I may just buy one.
The SWR bridge is a circuit I am familiar with. I built an SWR bridge using this circuit for the 2200 and 630 meter bands (136 and 475 kHz). I used two separate toroids made with number 77 material.
73, Zack W9SZ
I had forgotten that QRPGuys makes a nice little power meter accessory. ? for $40.? It was very easy to put together and includes a QRP dummy load on the board.? I think I built it in one night.? I have it sitting on a shelf under my station monitor.? It is battery operated so I only connect it when I need to verify power and my other meters.? It is a very handy device.? You need to wind the transformer but that is the hardest part of the kit.? It is very small and there is a 3D printed box that you can make too.? They use PayPal as an interface for payment and shipping.? Please see their for details.
--
Al Skierkiewicz
WB9UVJ
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There are SWR meters that also measure power.? Has switch for selecting which mode.? I have a $20 dual meter that has power and SWR and a low 15W and 100W position.?
When getting any SWR or power meter make sure it is made for your frequency range.? Many are for CB and work ok at 27 MHz, but not so accurate at lower HF bands.
All Hams, IMHO, should have SWR meters, no matter the bands of interest.? Is essential for antenna work.
73, ron, n9ee/r Ron Wright, N9EE/R Hernando Co ARES EC
Spring Hill, Florida also n9ee55@...
On Thursday, June 27, 2024 at 05:42:46 PM EDT, John D Erskine VE7MHI VA7OTC via groups.io <va7otc@...> wrote:
On 2024.06.25 06:37, Michael Newbury wrote:
> A swr meter aint gonna give you a power reading is it, its gonna give
> you a swr reading, unless you get something like a cross needle
> power/swr meter or the like, as for the mulitmeter, err i dont think
> so.
>
> Mick SA4MDN
Hi Mick,
Three of my bridges do.
73, John
--
John D Erskine
VE7MHI? VA7OTC
CN88hk? VA7RCN
Victoria, B.C.
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All Hams, IMHO, should have SWR meters, no matter the bands of interest.? Is essential for antenna work.
It's the 21st century, most hams should have a VNA by now ;-) And they can display swaaaar too. All for the price of a Mc Donalds Happy Meal these days,? far more versatile and educational than a swaaaaar meter on it's own. As for common power meters, well the problem with those is that they are additive types unless you use something like a Bird with a frequency selective slug, otherwise the power readings can be innacurate. Additive types relying upon simple diode detectors for example will not be much use of the TX has spurious emissions they get added to the reading, as do harmonics. For example 1st, 3rd and 5th harmonics can add to the readings. But in fairness if you're just looking to read the power of something like a properly functional FT817 where filtering is working correctly and you just wish to customise the power settings or check supply voltage vs power output then a bog standard power meter is good enough. But no good for golden screwdrivered rigs, homebrew and malfunctioning PA's. You might need a speccy analyzer for that too, but they are cheap now. Just give up eating donuts for a month and you can afford something like a TinySA Ultra (and you'll be healthier too). All sorted. 73 de Andy G0FTD
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on3plz
Michael Newbury SA4MDN
M0RON
Al WB9UVJ
Ham Radio
Fred-N7PN
Mike Dinolfo
John D Erskine VE7MHI VA7OTC