Frequency Counter advice

[jim111]

I am looking for a good frequency counter. Budget is around $500.
The primary use is for aligning 2 way radios.

All suggestions are welcome.

[jonpaul]

accuracy needed # digits, % ? Freq range min max?

2 way radios can be anywhere from low band SW, FM, VHF, or UHF bands, to name a few.

Jon

[jim111]

accuracy needed # digits, % ? Freq range min max?

2 way radios can be anywhere from low band SW, FM, VHF, or UHF bands, to name a few.

Jon

Frequency range 1.8 MHz to 500 MHz,
accuracy would like +/- .1 ppm, may not get that in this price range,
at least 9 digits on the counter.

Will be using it to align PLL/VCO's so it needs to be able to work with very low input voltages.

[bob91343]

My venerable HP 5328A can do all that.  They are available for not too much money.  Try to get one with the oven oscillator 10811 I think it is.  There are various options and mine will go to about 700 MHz and can resolve 0.1 Hz with 10-second count time.  The VHF coverage is with one of the high frequency options.

[xmo]

Your frequency counter budget might be better off applied toward a service monitor or spectrum analyzer.  Both of these are essential for servicing two-way radios.

I have been aligning two-way radios for many years and although I have several frequency counters, I find that I never use them.   I always set a radio's frequency using a service monitor (aka communications system analyzer or RF test set).

For measuring low level signals, such as your VCO example, many modern spectrum analyzers have a built in frequency counting function, which - when enabled - stops the sweep at the center and actually counts the input signal frequency with the same accuracy as a frequency counter would have. (based on the respective instrument's time base accuracy)  Plus, with the spectrum analyzer, you can measure the precise level of the VCO and observe it's stability and settling characteristics.

With the capabilities of a modern spectrum analyzer, I find it hard to envision an application for a standalone frequency counter.

[Electro Fan]

Maybe one of these....

https://www.ebay.com/itm/BG7TBL-FA-2-6GP-6G-Frequency-Counter-Power-detection-frequency-meter-11-bits-SEC/143670768349?hash=item217371f2dd:g:eYYAAOSwi8pfJSF5

... taking a 10 MHz reference signal from one of these....

https://www.ebay.com/itm/BG7TBL10MHz-LCD-GNSS-DISCIPLINED-OSCILLATOR-Support-GNSS-GPS-BDS-GLONASS-GALILEO/124281373714?hash=item1cefbf4412:g:ZeQAAOSw99hfJSF8

... and keep ~$100 for beer

[jim111]

Thanks for all your suggestions.

[Electro Fan]

accuracy needed # digits, % ? Freq range min max?

2 way radios can be anywhere from low band SW, FM, VHF, or UHF bands, to name a few.

Jon

Frequency range 1.8 MHz to 500 MHz,
accuracy would like +/- .1 ppm, may not get that in this price range,
at least 9 digits on the counter.

Will be using it to align PLL/VCO's so it needs to be able to work with very low input voltages.

BG7TBL FA-2 spec’d to work down to -20bBm up to ~5GHz, and down to -50dBm up to 550MHz

—-

CH1 Frequency Accuracy:
0.1s Gate Time: 0.001Hz@10M
1s Gate Time: 0.0001Hz@10M
10s Gate Time: 0.00001Hz@10M
             
CH1 Test Speed: 11 bits/second@10MHz
CH1 Power Test Range: -50dBm~+20dBm, 1M~550M@50 ohm
CH1 Power Test Accuracy: 0.5dB@10MHz
CH1 Connector Type: BNC

Introduction of CH2:
CH2 Frequency: 30MHz-6GHz
CH2 Input Impedance: 50 ohm
CH2 Power Accuracy: 1dB@2.45GHz

CH2 Frequency Accuracy:
0.1s Gate Time: 1Hz@1GHz
1s Gate Time: 0.01Hz@1GHz
10s Gate Time: 0.001Hz@1GHz
           
CH2 Input Power: -20dBm~+13dBm@0.5~5G
CH2 Connector Type: SMA

CH1 Frequency Accuracy:
0.1s Gate Time: 0.001Hz@10M
1s Gate Time: 0.0001Hz@10M
10s Gate Time: 0.00001Hz@10M
             
CH1 Test Speed: 11 bits/second@10MHz
CH1 Power Test Range: -50dBm~+20dBm, 1M~550M@50 ohm
CH1 Power Test Accuracy: 0.5dB@10MHz
CH1 Connector Type: BNC

Introduction of CH2:
CH2 Frequency: 30MHz-6GHz
CH2 Input Impedance: 50 ohm
CH2 Power Accuracy: 1dB@2.45GHz

CH2 Frequency Accuracy:
0.1s Gate Time: 1Hz@1GHz
1s Gate Time: 0.01Hz@1GHz
10s Gate Time: 0.001Hz@1GHz
           
CH2 Input Power: -20dBm~+13dBm@0.5~5G
CH2 Connector Type: SMA

[fourfathom]

BG7TBL FA-2 spec’d to work down to -20bBm up to ~5GHz, and down to -50dBm up to 550MHz

—-

CH1 Frequency Accuracy:
0.1s Gate Time: 0.001Hz@10M
1s Gate Time: 0.0001Hz@10M
10s Gate Time: 0.00001Hz@10M
             

To get that accuracy you need an external 10 MHz reference with zero frequency error.  Otherwise that's just resolution.
Fortunately, a GPSDO can be pretty inexpensive.  I use the Bodnar Mini GPS Reference (http://www.leobodnar.com/shop/index.php?main_page=product_info&cPath=107&products_id=301).  Since it uses a VTCXO it doesn't have as good holdover as a GPSDO with an OCXO, but as long as you have a stable GPS signal it does the trick.

[Electro Fan]

BG7TBL FA-2 spec’d to work down to -20bBm up to ~5GHz, and down to -50dBm up to 550MHz

—-

CH1 Frequency Accuracy:
0.1s Gate Time: 0.001Hz@10M
1s Gate Time: 0.0001Hz@10M
10s Gate Time: 0.00001Hz@10M
             

To get that accuracy you need an external 10 MHz reference with zero frequency error.  Otherwise that's just resolution.
Fortunately, a GPSDO can be pretty inexpensive.  I use the Bodnar Mini GPS Reference (http://www.leobodnar.com/shop/index.php?main_page=product_info&cPath=107&products_id=301).  Since it uses a VTCXO it doesn't have as good holdover as a GPSDO with an OCXO, but as long as you have a stable GPS signal it does the trick.

That's why I suggested both....

---

https://www.eevblog.com/forum/testgear/frequency-counter-advice/msg3493400/#msg3493400

Maybe one of these....

https://www.ebay.com/itm/BG7TBL-FA-2-6GP-6G-Frequency-Counter-Power-detection-frequency-meter-11-bits-SEC/143670768349?hash=item217371f2dd:g:eYYAAOSwi8pfJSF5

... taking a 10 MHz reference signal from one of these....

https://www.ebay.com/itm/BG7TBL10MHz-LCD-GNSS-DISCIPLINED-OSCILLATOR-Support-GNSS-GPS-BDS-GLONASS-GALILEO/124281373714?hash=item1cefbf4412:g:ZeQAAOSw99hfJSF8

... and keep ~$100 for beer

---

I think the BG7TBL GPSDO uses an OXCO rather than a VTCXO.

BG7TBL makes a variety of products.  This one might be a cost-effective solution for a 10 MHz reference signal to drive a counter (if the counter has a 10 MHz ref input).  But it might or might not work for the OP as it has a 13 dBm spec - although this would drive the counter, and the counter would be used with the radio gear, so it might be ok.

https://www.ebay.com/itm/By-BG7TBL-10MHz-OCXO-Frequency-Standard-Sine-Wave-Output/174517025907?hash=item28a2067c73:g:3ZUAAOSwrXhfrmRy

[jim111]

How about the B&K Precision 1823A Universal Frequency Counter 
with a Leo Bodnar Precision GPS Reference Clock?

[Electro Fan]

How about the B&K Precision 1823A Universal Frequency Counter 
with a Leo Bodnar Precision GPS Reference Clock?

from the 1823A manual...

INT/EXT TIME BASE SELECTOR:
Selects the source of the time base. EXT.STD. IN sets up BNC as a nominal 600 Ω input impedance path for an external 10 MHz time base signal. INT. STD. OUT sets up BNC to monitor the internal time base signal.
INT/EXT TIME BASE BNC:
Provides a connector through which the internal time base signal can be monitored or through which an external time base signal can be applied (see item above). The external signal should have a voltage range of 1.5 V~5 V rms.