BG7TBL FA-2 User manual

1
BG7TBL FA-2 Frequency Counter Vs. 2A
USER MANUAL
Original Copyright @2019 BG7TBL.All rights reserved.
Vs.1 had Chinese characters removed and with notes in [] by Don Latham. In Vs. 2 text and
pictures were edited for clarity. Type face was changed to New times Roman bold. Some
descriptions were paraphrased into English commonly used in the USA by KM6FQV. No
information was added or deleted.
This manual describes how to install and use FA-2 frequency counter.
For assistance, contact: WUTONG electronic Longhua Shenzhen Guangdong CHINA
http://bg7tbl.taobao.com
http://bg7tbl.taobao.com
TEL/VX: 0086-134 2795 9750
Q Q: 1630 2767
Email: [email protected]/[email protected]/[email protected]
Date: 2019-08-19
CONTENTS
1
Key Features
1
2
Overview
1
3
Specifications
2
4
Quick Start
3
4.1
Rear Panel
3
4.2
Front Panel
3
4.3
LCD display data
4
4.4
Connect PC
5
4.5
USB Config commands
6
4.6
Use notes
6
5
Block diagram
-
6
FAQ
7
1 Key Features
1. High speed, high precision, up to 11 digits/second@10 MHz
2. CH 2 input up to 6GHz
3. High precision internal OCXO, supports external 10 MHz reference frequency
4. Statistic functions: display average, max, min, p-p frequency.
5. With USB port, connect to PC, data compact HP53131 mode
6. CH 1 with power, dynamic range up to 60dB,
2. Overview
The FA-2 frequency counter is high precision, high speed, with statistical function, auto ranging
input frequency. It is convenient for long-term monitoring of external frequency changes. Channel
2 can measure frequencies up to 6 GHz using either the internal OCXO, or an external 10MHz
standard.

2
3 Specifications: Type: FA-2
CH 1 frequency range：1Hz-200 MHz
CH 1 input impedance: 50 Ohm/1M OHM
CH 1 input sensitivity：50 Ohm: 25mVrms-2Vrms
1M Ohm: 25mVrms-2Vrms
CH 1 frequency resolution 0.1s: 0.001 Hz @ 10 MHz
1s: 0.0001 Hz @ 10 MHz
10s: 0.00001 Hz @ 10 MHz
CH 1 test speed: 12 digits/second @ 100 MHz - 200 MHz
11digits/second @ 10 MHz - 99.999999 MHz,
10 digits/second @ 1 MHz - 9.999999 MHz
9 digits/second @ 0.1 MHz - 0.999999 MHz
8 digits/second @ 90 KHz - 99 KHz
8 digits/second @ 1 Hz - 89.999 KHz
CH 1 power test range -50 dBm to +20 dBm from 1 MHz to 550 MHz @50 Ohm
CH 1 power accuracy: 0.5 dB @10MHz
CH 1 connector type: BNC
CH 2 frequency range: 30 MHz - 6GHz
CH 2 input impedance: 50 Ohm
CH 2 frequency resolution：0.1s: 1 Hz @ 1GHz
1s: .01 Hz @ 1GHz
10s: 0.001 Hz @ 1GHz
CH 2 input power range: -20 dBm- +13 dBm @0.5-5GHz,
CH 2 connector type: SMA
Gate times: 0.1 Sec, 1 Sec, 10 Sec
Internal frequency standard: 10MHz OCXO. Ageing: 0.5Hz/year
10MHz reference frequency output power: +4 dBm
External reference frequency input level range: 0 dBm to +20 dBm
Run mode: CH1 frequency
CH1 statistics
CH2 frequency
CH2 statistics
Front panel: MODE, change mode
GATE: change gate time.
RST: restart test
CH1: channel 1 input
CH2: channel 2 input
Rear panel: 10MHz Ref Input
10 MHz REF Output
USB Printer port
STD ADJ: internal OCXO frequency adjust
Power switch
DC input connector

3
Statistics mode data type: Average, Max, Min, & P-P
Power : DC11.7-12.5V, startup: less than 0.4A, stabilized: less than 0.2A
Size: L X H X D = 106 X 55 X 105 mm weight: 350g
Accessory provided: DC12V adapter 1pcs [power supply]
Quick Start
4.1 Rear Panel
1. 10MHz frequency standard
Input and output.
2. USB port, chip is FT232RL,
USB driver available from
ftdi web site.
3. Internal OCXO frequency
adjust.
4. Power On/Off
5. DC12V input
4.2 Front Panel
1: 2864 LCD
2: MODE key: turn / run mode
3: GATE key, change gate time
4: RST key:
Restart Test,
RST + GATE,
Open/Close CH 1 LPF,
RST+MODE,
CH 1 Select 50R/1MR
5: Channel 2 input
6: Channel 1 input

4
4.3 LCD display data when using CH 1
1: CH 1 input power
2: Frequency display
3: Units
4: Gate time，0.1s, 1s, 10s
5: Inside/outside frequency
Standard [automatically
detects external reference]
6: CH 1 input impedance,
1 Meg or 50 Ohm
7: Gate state display: *indicates
gate is open.
8: Display: P means high precision
mode [PLL Locked]
9: 150 KHz LPF
Statistics Displayed:
1. 1 to 4,000,000,000 status
points.
2. Latest frequency reading
3. Average value
4 Max value
5 Min value
6. Peak to Peak value
7. Input impendence, 50 or
1Meg Ohm
8. Reference being used
[automatic switching]
9. Gate Time Used
10. LPF select

5
Channel 2 frequency test mode
1. Latest frequency reading
2. Reference used
3. Gate time setting
*P reference for CH 1 FREQ mode [presumably same as CH 1, needs to be checked? [P is not
shown here] reference channel 1 statistics mode [Think this means for reading details?]
Channel 2 statistics mode:
4.4 Connecting to a PC
Use the rear print port to connect to the computer USB port. USB chip type is FT232RL [If a
driver is needed]

6
4.5 USB Config command [NEEDS THOROUGH TESTING]
Default baud rate is 9600bps, ascii encoding
$R*press RST key, return KEY RST ROK<CR><LF>
$M*press MODE key, return KEY MODE MOK<CR><LF>
$G* Press GATE key return KEY GATE GOK<CR><LF>
$CXX* XX:0-63, setting LCD contrast, save in EEPROM, return SET LCD
CONTCOK<CR><LF>
$BXXXXX* setting baud rate, XXXXX 00480, 00960, 01920, 03840, 05760, 11520, Power off
without saving, return BOK<CR><LF>
$S* read statistics data
The following instructions are saved when the power is turned off:
$E2020* power up select CH1 frequency mode
$E2121* power up select CH1 frequency statistics mode
$E2222* power up select CH2 frequency mode
$E2323* power up select CH2 frequency statistics mode
$E3030* CH1 select 50R
$E3131* CH1 select 1MR
$E3232* Beep On.
$E3333* Beep Off
$E3434* open high precision mode [No idea what this does, comments?]
$E3535* closed high precision mode, all input frequency is 8 digits/second
$E3737* CH 1,closed CH 1 LPF
$E4040* select CH 1= 50R, input 10M 0dBm, calibration power meter used with $E4141*
command
$E4141* select CH1=50R, input 10M -20dBm, calibration power meter
4.6 Use notes
Keep away from high temperatures, and also from interfering signals. Power input must be less
than DC12.5V
5 Block diagram
[not in this document]

7
6 FAQ
Q : How can I know if the counter is operating properly?
A : Connect the rear panel 10 MHz reference output to the front panel CH 1. The LCD should
display 10 MHz. This means the counter is functioning properly.
Q: When measuring low frequencies, the display is not accurate or is unstable.
A: Enable LPF