CB and Ham Radio Techs Love Their Bird Wattmeters

[vk6zgo]

My takeaway, R&S was limited to 25MHz min,  120W Avg.   

At 2:24, it states the sensor can be used with the NRT2 meter or a PC with the virtual NRT PC software.  It shows the connector but never talks about how this would connect to the PC.  I would have guessed the PC connects to the NRT2 and requires it to talk with the sensor.   But that is not what the video claims.   

CBers and hams need to yell "audio" into the mic and watch the meters live.  There was no mention how fast the bar graphs  are updated.  The Bird 43 is fast enough for both groups.  We saw that one with the PC interface running at 1Hz and the ham/CBer was pretty upset how useless it was.  I would think something basic like the update rate would be one of the first things mentioned and demonstrated in a video like this.   I didn't see a mention of minimum power or accuracy.   

The homemade one I demonstrated had maybe a 2kHz update rate.  I would need to go back and look.   I think I demonstrated it with signal levels as low as -30dBm.   Downside to that unit was my home made coupler was limited to about 50MHz.  I could have possibly characterized it and then compensated for the non linearity in software but as it was, I just used a simple point slope and called it a day.   There was a third or fourth order polynomial fit to that Bird 43 analog meter graphics I ripped off.   Far more math to get that to work.   

"Fuuunnnyyy thhiiinng", I have never yelled "Auuuddddiiiooo" into a microphone in my life, nor heard a ham, CBer, or anyone else do so, except the CB "Gurus" on Youtube, who seem to delight in it

The usual test is to check the power on CW, then switch to SSB & say, if on a test load, "Testing, testing, 1, 2, 3".

On an antenna, a short burst of CW, followed by (in my case) "VK6ZGO Testing" or, if I expected someone to answer me, "CQ Test, CQ test this is VK6ZGO calling & testing."

Of course, a real test of an SSB transmitter ideally requires a two tone generator, even more ideally with a spectrum analyser as the device to look at the output.

Back in the "bad old days" at my old work, we tested our ISB comms Tx with a two tone generator & a selective voltmeter built into the exciter unit, to check intermods & channel to channel crosstalk.
For actual output power the Transmitters also had some quite good meters built in, which would show PEP.

Hell, that was so long ago that the exciters used Musa coax connectors!!

[joeqsmith]

The CBer's need 10kW and hams would want their 160 meter.    Guessing these groups are not the target.

We don't really design for or market to CBers or hams, even though we have quite a few hams working for Rohde & Schwarz, including Dr. Rohde himself (N1UL).  He's quite active on the bands and is also a strong supporter of / advocate for the amateur radio community.

A lot of the market for professional directional power sensors is for people who want to leave the sensor inline all the time and remotely monitor it.  For people who just want to make occasional measurements, most just use directional couplers and terminating power sensors (and pads, where needed).  I discuss this in an upcoming video.

I personally wouldn't try and promote my products in a thread about CBers and hams that don't provide the same or better performance than their beloved Bird.  Suggesting the people who started the company are hams has little to do with the product itself. 

... we have quite a few hams working for Rohde & Schwarz, including Dr. Rohde himself (N1UL).

That must have come as a shock to the arrogant assholes posting in this thread.

That's a poor attempt of trolling, even for you.   I doubt you will find too many people who think professionals don't have hobbies.   We have discussed a few of them before. 

[joeqsmith]

"Fuuunnnyyy thhiiinng", I have never yelled "Auuuddddiiiooo" into a microphone in my life, nor heard a ham, CBer, or anyone else do so, except the CB "Gurus" on Youtube, who seem to delight in it

The usual test is to check the power on CW, then switch to SSB & say, if on a test load, "Testing, testing, 1, 2, 3".

I would guess that the majority of the videos I had watched on Bird and other Watt meters was CBers, but the problem is still the same.  The display would need to be fast enough to keep up with the voice.   

From a previous post, showing update rate of a Coaxial Dynamics vs early version of my homemade meter.   I was hoping R&S would post a video showing their product in action.     

[pdenisowski]

I personally wouldn't try and promote my products in a thread about CBers and hams that don't provide the same or better performance than their beloved Bird. 

Sorry if you felt that I was trying to promote R&S products - I've stated many times in this thread (and others) that we don't design for or market to the hobbyist / ham radio market.   And every time I've posted information about our own directional power sensor (since I assume Bird is developing something similar), it's always been at the request of others posters, including yourself

I was hoping R&S would post a video showing their product in action.     

I would think something basic like the update rate would be one of the first things mentioned and demonstrated in a video like this.   I didn't see a mention of minimum power or accuracy.   

Regarding

Suggesting the people who started the company are hams has little to do with the product itself. 

Well, Dr. Rohde is actually the son of one of the founders. 

My observation was simply that although R&S does have a lot of hams and is very supportive of the ham radio community, we still don't make products that target that market.  We aren't supporting the ham community because they're potential customers (because they usually aren't), we support them because they're fellow hams

But again, my sincere apologies if you felt that I was somehow trying to "promote" R&S products.  Just theorizing on the upcoming Bird product and how it might compare technology-wise with other current-manufacture directional wattmeters.

[joeqsmith]

But again, my sincere apologies if you felt that I was somehow trying to "promote" R&S products.  Just theorizing on the upcoming Bird product and how it might compare technology-wise with other current-manufacture directional wattmeters.

No need for an apology.  I was just surprised that if you were going to promote a product, it wouldn't offer the same basic functionality that has been discussed here. 

.....developing something similar), it's always been at the request of others posters, including yourself

I only asked because you initially posted something about your products assuming they would fit the needs of the hams/CBers.  By asking, as least readers will know, so it's not like it was a wasted effort.

[metrologist]

...  If it does have a PC interface, hopefully it can update faster than 1Hz.

I'm a little lazy now to look into the details. The brochure posted later indicates a measurement time of 180 ms, in the golden 2W deadkey, 20W swing range into your heater.

I'm not sure how you would spec bar graph speed, but the NRT2 bar graph is very, very fast compared to anything else I've seen.

Fast as fast might not be fast enough. I would expect it to be faster than the measurement time.

From a previous post, showing update rate of a Coaxial Dynamics vs early version of my homemade meter.

joeqsmith for President....of wattmeter product design and marketing. 

[shabaz]

..including Dr. Rohde himself (N1UL).

Interesting! About five years ago, I was searching for some journal articles that were in old "Ham Radio" issues (a magazine that isn't published any more). So, I hung out on eBay for months, and eventually found someone willing to ship me a huge box of vintage Ham Radio magazines overseas. The content is quite technical, unlike a lot of hobby electronics magazines these days, so I still find it relevant to read.

I always wondered if the Ulrich Rohde who wrote some of the articles in those Ham Radio magazines was of R&S fame. I assumed Rohde may be a popular name, so I wasn't sure. He had a different callsign back then in those articles: DJ2LR.
There were in-depth articles concerning RF mixers, and oscillators, from memory.

[pdenisowski]

I always wondered if the Ulrich Rohde who wrote some of the articles in those Ham Radio magazines was of R&S fame. I assumed Rohde may be a popular name, so I wasn't sure. He had a different callsign back then in those articles: DJ2LR.
There were in-depth articles concerning RF mixers, and oscillators, from memory.

Yeah, that was Dr. Rohde - DJ2LR is his German call sign.  He's a rather prolific author - several hundred articles in this bibliography (German only, sorry!)

[shabaz]

Wow, this would make quite an engineering book if there were one day an omnibus containing all of them.
Anyway, I'm looking forward to downloading some of these and looking through them.

[vk6zgo]

"Fuuunnnyyy thhiiinng", I have never yelled "Auuuddddiiiooo" into a microphone in my life, nor heard a ham, CBer, or anyone else do so, except the CB "Gurus" on Youtube, who seem to delight in it

The usual test is to check the power on CW, then switch to SSB & say, if on a test load, "Testing, testing, 1, 2, 3".

I would guess that the majority of the videos I had watched on Bird and other Watt meters was CBers, but the problem is still the same.  The display would need to be fast enough to keep up with the voice.   

From a previous post, showing update rate of a Coaxial Dynamics vs early version of my homemade meter.   I was hoping R&S would post a video showing their product in action.     

The plain old meter movement on Birds & the like doesn't really "keep up with the voice" either, as its ballistics are anybody's guess.
VU meters have a standard specified ballistic characteristic, but they don't really keep up, either.
"Peak Programme meters" come a lot closer, but not quite.

"Peak power" meters with a moving coil meter usually have simple CR "peak & hold" circuits so stretch any peaks faster than their time constant plus are still captives of moving coil meter ballistics.

The advantage of digital circuitry is that you can produce a nice "rendered" pretend M/C meter with whatever ballistics your heart desires.
The "S" meter/output power meter on some Ham radios is just such a rendered display.

The usual reason for a speech check with an SSB ham radio is a "rough check" that the power is peaking up roughly in the same region as the power shown on CW.
The things have"mike level" controls which, if incorrectly set can cause distortion & possible overdrive of the output stages.

[joeqsmith]

The plain old meter movement on Birds & the like doesn't really "keep up with the voice" either, as its ballistics are anybody's guess.
VU meters have a standard specified ballistic characteristic, but they don't really keep up, either.
"Peak Programme meters" come a lot closer, but not quite.

From the perspective of the people holding the Bird as the gold standard, they keep up.  Some add their aftermarket peak detectors.  I'm sure it's obvious even to the hams that the mechanical movement is not going to track at even the low frequencies I can still hear.  Of course, nor can the home made meter I demonstrated.  I think I ended up with a 2kHz 1-pole filter on the inputs.  Then there is a limit how fast I sample and get the data to the PC (maybe 5kHz?).  Then how fast the PC can update the screen.  But that's not really the point I was trying to make. 

The advantage of digital circuitry is that you can produce a nice "rendered" pretend M/C meter with whatever ballistics your heart desires.

No doubt I could have bought a few Bird meters, measured the transfer function for the displayed power, then simulated that in software.  The hardware is certainly capable.  For cosmetics, I did add a dampening filter to slow the needles while they return to zero.   Sadly, but not surprising, none of the ham/CBers joined in with their own homemade in-line Watt meters to show me how it's done.   

Interesting! About five years ago, I was searching for some journal articles that were in old "Ham Radio" issues (a magazine that isn't published any more). So, I hung out on eBay for months, and eventually found someone willing to ship me a huge box of vintage Ham Radio magazines overseas. The content is quite technical, unlike a lot of hobby electronics magazines these days, so I still find it relevant to read.

   

I have a few paper magazines from the 60s and earlier.  It's amazing just how technical these are.  But that's my point.  Times changed.  Current hams can point to the past but today I see little interest in the technical side of things.  Sure, we can point out a few individuals but we can't suggest they represent the norm. 

BTW, I think many of these old magazines are now archived in PDF format.     

[Wallace Gasiewicz]

I do a lot of work on Ham and CB Radios.   
I use an HP 8935 service monitor for most of my radio analyzing.  It is especially nice to see a SSB signal 1.5 KHz off center freq when putting in a 1.5 KHz audio signal.  I have set up microphones with BNC connections so that I can just connect the 50 mV audio output of the service monitor into the mic input easily.     
If I really wish to know the watt output I use an Agilent E7495 Service Monitor with a Power Meter in it and an HP sensor.  Along with the HP Attenuator, of course.    My HP 7426 Selective Level  Unit also does a very good job, and it is selective about the frequency it is measuring.   However, I have never found a case where I need to know the transmitter output that accurately.   
None of these things are peak reading.    But if you put a constant audio input into a transmitter the peak is the same.
I use an old Analog Wattmeter in line to keep an eye on output normally, because it is more convenient, and I can see it easily.    .   
I can align all sorts of brands of analog wattmeters so that they read very well at their midpoint of the mechanical meter. None of the meters I have seen are linear. Most are not very good at all outside of their midpoint reading.   The Bird Meters are the closest thing I have seen to linear in the analog class.   
In practical use with AM and SSB, a peak reading meter is almost necessary but these things are also all over the map in their accuracy. But there is no need to be accurate. A Wattmeter that is close and has SWR capabilities is all most people need.

The CBers are enthralled with the "swing" of the analog meters on peak reading.  You can sell them a meter that swings all over the place and they are happy.  So in a lot of cases a meter with abnormal ballistic characteristics is preferred.   

If you really wish to know your transmitter output accurately, I have seen one of these things used,   

http://www.telepostinc.com/LP-500.html     

It is a terrific piece of equipment, if you really want to know the output of your transmitter and keep an eye on your transmission line and antenna.  I think this is an excellent piece of equipment that will give you more info than you need.     

To change the subject a bit:

I am thinking of trading in my HP Service Monitor and getting a R&S monitor.  I really like the blue color.  Perhaps pdenisowski can give me some points on the CMU 200.  As far as I can gather, without an attenuator the input is limited to 50 Watts.

[pdenisowski]

I am thinking of trading in my HP Service Monitor and getting a R&S monitor.  I really like the blue color.  Perhaps pdenisowski can give me some points on the CMU 200.  As far as I can gather, without an attenuator the input is limited to 50 Watts.

Although a lot (and I mean a LOT) of people have "repurposed" CMU200s, they are essentially cellular base station emulators, but it's hard to say if it would be a good fit for radio testing - I've never actually used it that way.

Our current radio test set is the CMA180 (which has 150W input power)

https://www.rohde-schwarz.com/us/products/test-and-measurement/wireless-tester-rf-analyzer-generator/rs-cma180-radio-test-set_63493-56068.html

I've tested most of my radios with it and it works well, but quite honestly, the CMA180 would probably be overkill (and over budget) depending on the kind of testing you're doing. 

I also made a few videos on the CMA180 - most are about avionics testing, but here are two purely "radio test" how-to presentations




Note that a lot of the "official" product pictures show amateur radios as the DUTs (like the Elecraft KX2)

[shabaz]

Interesting! About five years ago, I was searching for some journal articles that were in old "Ham Radio" issues (a magazine that isn't published any more). So, I hung out on eBay for months, and eventually found someone willing to ship me a huge box of vintage Ham Radio magazines overseas. The content is quite technical, unlike a lot of hobby electronics magazines these days, so I still find it relevant to read.

   

I have a few paper magazines from the 60s and earlier.  It's amazing just how technical these are.  But that's my point.  Times changed.  Current hams can point to the past but today I see little interest in the technical side of things.  Sure, we can point out a few individuals but we can't suggest they represent the norm.     

I get the feeling the amateur radio community is such a wide mix, that there are bound to be many members without any engineering background. From that perspective it's impressive that with what's inherently a technical-related hobby, the community have found ways to get people over the line and get them at least licensed, and then the hope is some continue the learning, but probably there are all manners of barriers, like education, health, etc., just like any wider community, so some get very experienced with what they can do practically, some might not be able to interact with others much and need lots of hand-holding, and others might avoid anything (say) math-heavy.

I don't know many amateur radio enthusiasts (I've only interacted via e-mail or Zoom calls with a dozen or so), so the above is heavy speculation, though.

I initially thought that may be the reason a lot of modern magazines are so lacking in technical content, but it's happened everywhere. Dr Dobbs was a great software-engineering journal, well worth the subscription, but somehow that didn't manage to survive. I really miss that magazine. Same with semi-technical TV shows, they've mostly disappeared or reduced to a husk of what they were. The days that kids would discuss the latest Tomorrow's World (and similar shows) in the school playground are maybe disappearing : (

BTW, I think many of these old magazines are now archived in PDF format.   

Thanks for that, I had missed that magazine was archived. It looks complete too.  Ham Radio is fully archived here!

[joeqsmith]

I get the feeling the amateur radio community is such a wide mix, that there are bound to be many members without any engineering background.
....

When I had a license, I had zero engineering background and not even a high school education.  It was just a matter of memorizing a few questions and learning Morse code.  I was in a club where the majority bought everything.   Most were only interested in blabbing on 2M.   Fast forward, a cell phone would have been perfect for them.   

[pdenisowski]

I get the feeling the amateur radio community is such a wide mix, that there are bound to be many members without any engineering background.

I had no engineering background when I got my first amateur radio license.  In fact, it was amateur radio that got me interested in electronics and RF, which eventually lead me to getting a Master's in EE and thus turned my hobby into my profession.

There are certainly a small number of very technical hams who *might* look down (somewhat) on hams who don't homebrew their station and antennas, etc. but my experience has been that amateur radio is very much a "big tent" that welcomes people of all technical and skill levels. 

Most of the people I work on CW (Morse code) send something other than the word "engineer" when we get to the obligatory exchange of professions 

[bd139]

Oh goody a ham subthread. You know how I like those 

Hams put me off amateur radio. First in the early 1990s. Then in the early 2020's. Many many more highly defective personalities, ego worshipping, thinking cults, creepers and charlatans than any other hobby I've been involved in. I don't want to go in that "big tent" again.

I've told this story before, but it outlines that it's not always true. Alpha ham at my local club was seen as a technically superior human being. He had a C&G cert in household electrical work from the 1970s to back this up. So I turn up and get the usual initiation ceremony (get the new guy a sausage roll and a can of coke quick - he looks like he needs a meal). This turns out to be a ragging about the immutable hierarchy in the club. I am invited to a repair session where the guy completely mutilates the LPFs on a Kenwood black box with Jesus' very own soldering iron after the owner mutilated them by keying down into a dead short. Radio surprisingly works afterwards even though the PCB looks like an Icelandic volcanic tundra. Well then we get talking and he finds out I was an EE. Pants are shit. There's a fox in the hen house. Shunned I leave for the priesthood may be upset if someone actually says "hang on a minute - what the fuck are you doing?".

The one high moment was a 2W CW contact half way across the planet on a radio you put together yourself. But once you've done that bit, it's boring. Found more interesting things to do anyway. And people I still email all bailed as well citing 2m as the main reason.

[shabaz]

Unfortunately any broad group will include some miserable members that are heavily detrimental to others. But not all are like that. A friend of mine spends a lot of his time preparing people from all skill-levels (most are often non-engineers) to sit their exams. His reward is simply to see them successfully pass. Most people are genuinely pleased when there are new members with skills to share with them.

I've not checked out my local amateur radio club at all. I got lucky and joined one much further away, full of friendly members, so I've had no incentive to check locally. I prefer Zoom meetings, to watch their PowerPoint presentations and see each other remotely. I miss the annual Xmas meet-up though because of the distance : (

[xrunner]

As far as joining ham clubs (or any other) I defer to what Groucho Marx said about that ... 

[shabaz]

It's a personal choice, of course, but from a birds-eye view, there's little difference between typing in this forum section (which accommodates ham radio) and typing an e-mail to an amateur radio group (which accommodates anyone). I don't think many clubs care about a radio license as a prerequisite to joining (I didn't have one, and they were still welcoming to all).

In both cases, one can dip in and out, ignore toxic stuff (which occurs on forums, too), and contribute where possible, if desired. One just happens to be slightly more local/regional often.

[Wallace Gasiewicz]

I have a HAM license and am interested in old equipment.   There is a long history of radio building and operating in my family since about 1920, my father was part of this history being a communications officer in WWII.  Other relatives have made their living in RF related industries.
And I am NOT an engineer, I dropped out of Engineering school the second year after my advisor told me that my degree would not guarantee that I would be able to drive a train.   I was devastated and all that education in calc and diffy Q was wasted.. I did ride in a caboose however (another story).   

There are all sorts of personalities in HAM Radio, any group that I have joined thru the years has an assortment of goofy folks. Bridge Clubs  all the was to expensive Country Clubs.  I suspect any sort of "club" attracts these folks.

[ftg]

...
I am thinking of trading in my HP Service Monitor and getting a R&S monitor.  I really like the blue color.  Perhaps pdenisowski can give me some points on the CMU 200.  As far as I can gather, without an attenuator the input is limited to 50 Watts.

I own a CMU200 and CRTU-RU.
And I would advice against trading in the service monitor and swapping over to CMU200.
While it can generate AM/FM/SSB test signals between 100kHz - 2700MHz, it can only really receive FM, and that is with the analog AMPS option in it (for CMU200, I don't know about CRTU-RU, mine only has AM and SSB modulations in the generator, no FM).
The AMPS option kainda sucks when it comes to tuning radios, as it does 30kHz channel step and is limited in other, fun ways.
The time domain power meter in both of them is quite usable for measuring the output power from timeslotted digital radios like DMR and TETRA, unlike older service monitors like R&S CMT.

As for the 50W input power tolerance, it depends on your unit.
My CRTU-RU (essentially CMU200 with sightly different software, with an additional box it could do WCDMA, I think?) is 50W capable.
But my CMU200 is 2W only. But friends have CMU200's with the 50W input option.

On the flipside, my CMU200 has two signal generators and not one, which makes it nice for adjacent channel, IM and mixer measurements.
The AUX generator cannot fit the machine if the 50W option is fitted.
So a unit with an installed AUX gen option will definitely not be 50W capable.

[pdenisowski]

Another "teaser" video from Bird about their upcoming product (October 8th)



Interesting narration / voice over style  ... wondering if I should do something similar in my next video

[xrunner]

Revolutionary.

Good word to toss around for marketing. Let's see if it holds up.

"Accuracy no matter the frequency ..."

No matter the frequency (unless it's outside of the product specifications). 

Yea and they used AI to make the complex signal measurement scene. I mean that guy is overwhelmed with complex digital signals to measure. I hope Bird's new instrument can help him out.

 

[metrologist]

Interesting narration / voice over style  ... wondering if I should do something similar in my next video

Yes please