Is it practical to own a frequency counter?

[Radiomatrix]

how many of you have a freq. meter?
What is an affordable model?
on my radio, a modification was installed decades ago when the NB button is depressed , an additional set of frequencies are realized.

 

[guitar_199]

Just one opinion here.......

if you are planning on repairing/aligning? A frequency counter is absolutely essential. The lions share of radios you see these days is going to be PLL...which means you have an adjustable VFO. The closer you set THAT.... the more accurate your unit will be aligned on both receive and transmit.

if you are planing on being a radio user? They can help you, ESPECIALLY if you have extra channels, unlocked clarifiers, external VFOs.... things like that. It would allow you to keep "tabs" on your radio's "transmit" which can infer how well the receive is tuned.

It is just a handy thing to have.

Sometimes the best place to find a decent one is on the used market.
I got a 1.3 Ghz Beckman for about $70 on a ham radio classifieds site.
You don't have to have anything that high for most purposes.... BUT.... the more digits it offers.... the more accurate you can be. Mine is 8 full digits.... so it can read 27.xxxxxx (theoretically down to 1 hz accuracy). A 6 digit will only show you down to the '100 hz' accuracy. And that MAY be enough.... that is a decision for the person buying/using it.

 

[Radiomatrix]

Just one opinion here.......

if you are planning on repairing/aligning? A frequency counter is absolutely essential. The lions share of radios you see these days is going to be PLL...which means you have an adjustable VFO. The closer you set THAT.... the more accurate your unit will be aligned on both receive and transmit.

if you are planing on being a radio user? They can help you, ESPECIALLY if you have extra channels, unlocked clarifiers, external VFOs.... things like that. It would allow you to keep "tabs" on your radio's "transmit" which can infer how well the receive is tuned.

It is just a handy thing to have.

Sometimes the best place to find a decent one is on the used market.
I got a 1.3 Ghz Beckman for about $70 on a ham radio classifieds site.
You don't have to have anything that high for most purposes.... BUT.... the more digits it offers.... the more accurate you can be. Mine is 8 full digits.... so it can read 27.xxxxxx (theoretically down to 1 hz accuracy). A 6 digit will only show you down to the '100 hz' accuracy. And that MAY be enough.... that is a decision for the person buying/using it.

In a nutshell, nothing that sophisticated-No….on the repairing and aligning…at least not before your posted this, but a lot could happen before I die. (I think my radio has a phase lock loop.) i just thought having a freq. meter would be interesting to measure my signals…. More stuff to buy and learn about! Thanks

 

[TM86]

I have three. One is a Max-100A I got in the 80's for fixing someone's radio. Next one is a part of a BC-2000 base console that I need to fix. Third is my current go-to, a Fluke 1900A I got off eBay as "untested". It works perfectly.

Affordability comes down to budget. Figure out what you want to spend and then start looking in that price range. You can spend anything from a $9.00 kit off Amazon to thousands of dollars for high end gear. The more precision you think you need the more it's going to cost you. You can also find deals on eBay, etc. Sometimes they're bad deals, but deals nonetheless.

Don't hesitate to ask for opinions on specific gear here. Everyone will have something different to say about any given piece of gear, but you can at least get a consensus on if its known to be junk already.

BTW, the $9.00 kit? Yeah, don't do that unless you like building your own test equipment and then providing your own enclosure, power supply, etc.

 

[whiteastro]

They can help you diagnose if your radio is off frequency. I have a separate one for each of my Galaxy DX 979s because of Galaxies reputation of drifting and I bought a Dosy TFC-3001-S for my bench so I can check any radio including SSB radios to see if they need a trip to a radio shop. wish I had the knowledge and talent for alignment. 6 digit counter is sufficient for most purposes unless you want to get into repair work.

 

[Radiomatrix]

I have three. One is a Max-100A I got in the 80's for fixing someone's radio. Next one is a part of a BC-2000 base console that I need to fix. Third is my current go-to, a Fluke 1900A I got off eBay as "untested". It works perfectly.

Affordability comes down to budget. Figure out what you want to spend and then start looking in that price range. You can spend anything from a $9.00 kit off Amazon to thousands of dollars for high end gear. The more precision you think you need the more it's going to cost you. You can also find deals on eBay, etc. Sometimes they're bad deals, but deals nonetheless.

Don't hesitate to ask for opinions on specific gear here. Everyone will have something different to say about any given piece of gear, but you can at least get a consensus on if its known to be junk already.

BTW, the $9.00 kit? Yeah, don't do that unless you like building your own test equipment and then providing your own enclosure, power supply, etc.

I posted here because i was not searching on this thing incorrectly and my searches were not producing models to shop for.

 

[guitar_199]

In a nutshell, nothing that sophisticated-No….on the repairing and aligning…at least not before your posted this, but a lot could happen before I die. (I think my radio has a phase lock loop.) i just thought having a freq. meter would be interesting to measure my signals…. More stuff to buy and learn about! Thanks

One more thing to pay attention to.... the impedance of the input.
Sometimes they are on the order of 1 meg. Those you can poke around fairly freely.
SOME are 50 ohm (or switchable to 50 ohm). You have to be careful with any test equipment that has a 50 ohm input impedance. It will do it's BEST to imitate a dummy load for about 137 milliseconds... before it blows up. you can't just touch those to the output of a radio.

 

[nomadradio]

Hmmm. We keep a frequency counter hooked to an attenuator tapped off the workbench dummy load. This keeps the drive level to the counter's input safe. And it serves as a sanity test when a radio does something puzzling.

It's an HP brand from the 80s. Developed a fondness for them a long time ago.

But to set the internal frequencies in a radio to place its transmit/receive frequencies where they should be I prefer the "wireless" approach.

Feeding a counter's input from an oscilloscope probe would let you read a radio's internal frequencies, but the tip of that probe will frequently introduce a frequency error when you unhook it.

A ham HF transceiver new enough to be stable and accurately on frequency is one way we set those internal frequencies. A communications service monitor is nice. It will have a display showing the frequency error of what you're monitoring, but you don't have one of those.

I use an accurate 1 kHz tone source as a reference. A smartphone with the right app will do this just fine. The receiver gets tuned to exactly 1 kHz higher than the frequency we wish to set. Lower sideband gets selected, so that a carrier 1 kHz below the receiver's displayed frequency will produce a tone in the speaker exactly one kHz. To calibrate 10.240 MHz the radio would be tuned to 10.241 MHz. There will be an audible beat tone with both your 1 kHz reference and the receiver's speaker turned up. Tweaking the radio's trimmer adjustment until that beat tone gets down to about once per second, and you are now adjusted to within 1 Hertz. To do that by tapping into the circuit with a counter probe will be annoying, since the counter's gate will have to be set for 1 second update speed. Too much like playing a violin for me.

And a counter is better than nothing, but beware errors it can add to the setup.

73

 

[brandon7861]

I found a EZ FC7015U 150MHz counter on ebay a few years back for $50 that has works flawlessly. It was a bit tricky getting it calibrated to WWV as the trim cap inside the oscillator can is very touchy, but it has been spot on since. That model has its pros and cons. The pros are that its cheap, very accurate, and has a 1MΩ input impedance with a max voltage of 250V (so the front end is nearly idiot-proof). The cons are that for 1Hz resolution, the capture time is 10 seconds, and it tends to get jumpy when the signal is lower than 100mV or so pk-pk at the counter port.

Even with its high input impedance, the coax that leads to it is still too capacitive, and with a regular 10x probe, there is not enough signal for that counter to read accurately on all CB radio test points.

I ended up making an active probe just for the counter using a BF998 and a couple bjt's. The active probe you build (or buy) does not have to have a flat response over a GHz like the expensive ones though (thats where the high price of HP probes comes from), if all you are doing is counting frequency with it.

Ebay has a BF998 probe pre-assembled (no shielded enclosure though) for $30, but it will also need a small 20dB amp module ($10 on amazon) after it as the probe design outputs 50Ω at -20dB down. At -20dB without the amp after it, the buffered signal can still be under the counters threshhold.

I now see the same counter I have is about $150, so expect to wait for a deal to pop up or spend $150 to $200 total with the probe.

 

[Lkaskel]

how many of you have a freq. meter?
What is an affordable model?
on my radio, a modification was installed decades ago when the NB button is depressed , an additional set of frequencies are realized.

This was one of hurdles that I struggled to overcome when I started working on radios a few years back. Here is what I learned. I have no idea where you are in your tech understanding so I'll start at the begining rather than getting too technical. Lets break your quesion down into 2 thoughts based on what your (or others) expectations are:

1). The 1st is the basic need to know what channel/frequency you are on. This is similar to a radio like a Galaxy or a Cobra 148F for example. You will not be able to tune your radio to a VERY accurate reading but close enough to understand where you are (I'll explain that at the end of this response). I am assuming that you are looking to read the frequency at the antenna jack which means you would only be able to know that reading only when you are transmitting (although the radios with internal freq displays show during receive and tx). Thats not a problem but it is a limited amount of information. It does get the job done and there is nothing wrong with that. A freq counter of this level could be picked up off of Ebay for under $100 but you will need a sampler to connect it to the radio. Look up the BK 1805 as an example.

2). The second need is to get a super accurate reading and possibly want to connect it to test points inside the radio. These types of freq counters have the ability to give you more info and at a faster rate. That is important because if you are making adjustments in the radio you would want the reading instantaneously. These types of freq counters can be had off of Ebay for hundreds of dollars and would still need a sampler if you connect it to the antenna jack. Look up HP Hewlett Packard 5352B as an example.

Here are some very important details regarding freq counters and why they serve 2 different outcomes:

- Counter resolution. How mant digits can it display? What does that mean? For instance the very accurate frequency of channel 19 is 27.185.000. Those last 3 digits (000) are very important if you are aligning a radio but if you are just needing to know what channel you are on you can get by with 27.185. That's why some radios have the built in 5 digit counter. You would need to be sure how many digits it can display max (resolution). This is not the only consideration though. One other feature is the gate or period of the counter that plays into the amount of digits. See below.

- Gate or period. This is the speed at which the counter can read the frequency and display it. On the lesser expensive counters like the BK the more digits it displays the longer it takes to read and display the frequency. If you were looking to display the max digits it could it may take more than a second to display the results. If you were hoping to use it to make adjustments/alignments it really is handicapped because it does not display quickly enough. As you are turning an adjustment point this type may not update quickly enough to see what result you are looking for. The more expensive units can read/display those frequencies instantly no matter how many digits it is displaying.

In summary. The less expensive counters are perfect to display a frequency/channel during transmit. This is great if you have extra channels and just need to know where you are. The more expensive counters are what is needed if you are aligning radios or need accuracy and speed at those last 3 digits.

I hope this helps just a little.....

 

[guitar_199]

Hmmm. We keep a frequency counter hooked to an attenuator tapped off the workbench dummy load. This keeps the drive level to the counter's input safe. And it serves as a sanity test when a radio does something puzzling.

It's an HP brand from the 80s. Developed a fondness for them a long time ago.

But to set the internal frequencies in a radio to place its transmit/receive frequencies where they should be I prefer the "wireless" approach.

Feeding a counter's input from an oscilloscope probe would let you read a radio's internal frequencies, but the tip of that probe will frequently introduce a frequency error when you unhook it.

A ham HF transceiver new enough to be stable and accurately on frequency is one way we set those internal frequencies. A communications service monitor is nice. It will have a display showing the frequency error of what you're monitoring, but you don't have one of those.

I use an accurate 1 kHz tone source as a reference. A smartphone with the right app will do this just fine. The receiver gets tuned to exactly 1 kHz higher than the frequency we wish to set. Lower sideband gets selected, so that a carrier 1 kHz below the receiver's displayed frequency will produce a tone in the speaker exactly one kHz. To calibrate 10.240 MHz the radio would be tuned to 10.241 MHz. There will be an audible beat tone with both your 1 kHz reference and the receiver's speaker turned up. Tweaking the radio's trimmer adjustment until that beat tone gets down to about once per second, and you are now adjusted to within 1 Hertz. To do that by tapping into the circuit with a counter probe will be annoying, since the counter's gate will have to be set for 1 second update speed. Too much like playing a violin for me.

And a counter is better than nothing, but beware errors it can add to the setup.

73

I really like reading about this technique. Thanks!

 

[Radiomatrix]

This was one of hurdles that I struggled to overcome when I started working on radios a few years back. Here is what I learned. I have no idea where you are in your tech understanding so I'll start at the begining rather than getting too technical. Lets break your quesion down into 2 thoughts based on what your (or others) expectations are:

1). The 1st is the basic need to know what channel/frequency you are on. This is similar to a radio like a Galaxy or a Cobra 148F for example. You will not be able to tune your radio to a VERY accurate reading but close enough to understand where you are (I'll explain that at the end of this response). I am assuming that you are looking to read the frequency at the antenna jack which means you would only be able to know that reading only when you are transmitting (although the radios with internal freq displays show during receive and tx). Thats not a problem but it is a limited amount of information. It does get the job done and there is nothing wrong with that. A freq counter of this level could be picked up off of Ebay for under $100 but you will need a sampler to connect it to the radio. Look up the BK 1805 as an example.

2). The second need is to get a super accurate reading and possibly want to connect it to test points inside the radio. These types of freq counters have the ability to give you more info and at a faster rate. That is important because if you are making adjustments in the radio you would want the reading instantaneously. These types of freq counters can be had off of Ebay for hundreds of dollars and would still need a sampler if you connect it to the antenna jack. Look up HP Hewlett Packard 5352B as an example.

Here are some very important details regarding freq counters and why they serve 2 different outcomes:

- Counter resolution. How mant digits can it display? What does that mean? For instance the very accurate frequency of channel 19 is 27.185.000. Those last 3 digits (000) are very important if you are aligning a radio but if you are just needing to know what channel you are on you can get by with 27.185. That's why some radios have the built in 5 digit counter. You would need to be sure how many digits it can display max (resolution). This is not the only consideration though. One other feature is the gate or period of the counter that plays into the amount of digits. See below.

- Gate or period. This is the speed at which the counter can read the frequency and display it. On the lesser expensive counters like the BK the more digits it displays the longer it takes to read and display the frequency. If you were looking to display the max digits it could it may take more than a second to display the results. If you were hoping to use it to make adjustments/alignments it really is handicapped because it does not display quickly enough. As you are turning an adjustment point this type may not update quickly enough to see what result you are looking for. The more expensive units can read/display those frequencies instantly no matter how many digits it is displaying.

In summary. The less expensive counters are perfect to display a frequency/channel during transmit. This is great if you have extra channels and just need to know where you are. The more expensive counters are what is needed if you are aligning radios or need accuracy and speed at those last 3 digits.

I hope this helps just a little.....

Thank you. #1 details my basic curiosity and that would be terrific. In your summary is my situation….just would like to know where I am tx from. I am excited!

 

[Radiomatrix]

I found a EZ FC7015U 150MHz counter on ebay a few years back for $50 that has works flawlessly. It was a bit tricky getting it calibrated to WWV as the trim cap inside the oscillator can is very touchy, but it has been spot on since. That model has its pros and cons. The pros are that its cheap, very accurate, and has a 1MΩ input impedance with a max voltage of 250V (so the front end is nearly idiot-proof). The cons are that for 1Hz resolution, the capture time is 10 seconds, and it tends to get jumpy when the signal is lower than 100mV or so pk-pk at the counter port.

Even with its high input impedance, the coax that leads to it is still too capacitive, and with a regular 10x probe, there is not enough signal for that counter to read accurately on all CB radio test points.

I ended up making an active probe just for the counter using a BF998 and a couple bjt's. The active probe you build (or buy) does not have to have a flat response over a GHz like the expensive ones though (thats where the high price of HP probes comes from), if all you are doing is counting frequency with it.

Ebay has a BF998 probe pre-assembled (no shielded enclosure though) for $30, but it will also need a small 20dB amp module ($10 on amazon) after it as the probe design outputs 50Ω at -20dB down. At -20dB without the amp after it, the buffered signal can still be under the counters threshhold.

I now see the same counter I have is about $150, so expect to wait for a deal to pop up or spend $150 to $200 total with the probe.

Ευχαριστώ πολύ

 

[Radiomatrix]

McBazel SF-103

 

[Lkaskel]

Thank you. #1 details my basic curiosity and that would be terrific. In your summary is my situation….just would like to know where I am tx from. I am excited!

Awesome!! There would be nothing wrong with getting one of the lesser expensive ones and connecting it in. For a

Thank you. #1 details my basic curiosity and that would be terrific. In your summary is my situation….just would like to know where I am tx from. I am excited!

Awesome!! Connecting it to your setup is pretty straight forward. You will need a sampler so the "full power" of the radio is not sent to the freq counter. Try searching on *bay for RF Sampler Modulation Monitor as an example of what could be used. If you use an amp make sure that the sampler is BEFORE the amp!!!

Let us know how it works out.