FY6800 Signal Generator

In today’s postbag, the new Feeltech FY6800 dual channel Signal Generator, complete with UK power lead, two bnc test leads, USB lead and bnc-bnc lead. However the unit came with no instructions or other paperwork. I assume a manual will follow later. The unit arrived well-packed via FedEx.


Lovely to look at and extremely comprehensive in operation, the FY6800 is a compact unit that belies the vast range of functions it handles.

The opening:

No problems or packaging issues.



The FY6800

The FY6800 comes hot on the tail of the FY6600 which I received late last year. In the packaging came the unit and a box of leads as described. That’s it.

Feeltech.net downloads does not mention this unit but has only the FY6600 unit, however their web page refers to the FY6800 unit with 0.0000001hz to 60Mhz output at 0-20v.

The spec underneath originally referred in part to the earlier FY6600 – I’ll assume that’s a typo in the absence of a manual. In fairness the web spec does seem pretty comprehensive but some images and examples of use would have been good.

Here is the unit sitting on my bench, running, alongside a new meter and variable supply (space is at a premium in my temporary office here in the countryside).


And here is the back panel complete with UK lead.


I don’t yet have access to much of my test kit including scopes and so testing is right now severely limited, don’t start me on why. I’ll come back to this hopefully in June with a vengeance.

Meanwhile… if you recall my write-up on the FY6600, operation is straight forward with all controls on the front panel. I’ve done some audio testing without issue. The unit comes with a large number of preset waveforms and you can add your own.

On the downside after the unit had been running on my bench for a couple of hours, despite running only luke-warm, there was a distinct smell of burning through the vents in the back. I’ll put that down to newness as nothing appears to be burning. Temperature here in Northumberland is 20c. Toward the summer I’ll take this unit to Spain where the ambient temperature will be a lot warmer,

The product is described on the web as the “FY6800 programmable dual channel DDS function arbitrary waveform signal generator/pulse signal source/frequency meter”.

Note: the information below is taken straight from the Feeltech website. modified to indicate the 6800 and to to make the English translation better. I cannot accept responsibility for mistakes. I note the EEV blog has this info but unmodified.

The instrument adopts DDS direct digital synthesis technology to produce accurate, stable, low-distortion output signals. All parameters are calibrated by internal programs; standard PC software, all functions of the instrument can be controlled by the host computer software, and also can use the upper position.

The machine software saves the arbitrary waveform and saves the output waveform to the signal generator; the communication protocol is open, making secondary development very simple; large-scale integrated circuit, surface mount technology, high reliability, long service life and output short-circuit protection are all there, so all signal outputs can work under load short-circuit conditions.

1. The FY6800 uses a professional 14Bit high-speed D/A chip instead of a 12-bit D/A resistor network built with several inexpensive resistors. The higher the resolution, the smoother the waveform details. We recommend you use an oscilloscope to reduce the amplitude resolution and time-base to observe the details of the sine wave. The waveform detail and smoothness of the two solutions will be immediately obvious.

2. The FY6800 series sampling rate is upgraded to 250MSa/s and the waveform contour of the instrument is much clearer than earlier 200MSa/s sampling rate at the same frequency;

3. FY6800 series waveform memory depth is upgraded to 8192 * 14bits so that high-precision signal details can be restored.

4, the industry's original very practical VCO function, see the feature introduction.

5, FY6800 series phase resolution up to 0.1 degrees means users can more accurately control the delay of the two signals;

6, the signal output terminal uses pure copper material, not plastic coated zinc alloy material.

7, the instrument uses imported long-life keys which feel comfortable;

8. The first two-channel waveforms are displayed on the LCD interface at the same time.

9, 4 TTL outputs improve the usefulness of the instrument.

10, small signal performance is particularly good, the FY6800 can output 1mVpp  small signal amplitude resolution of 1mV, and steps include 1mVpp, 10mVpp, 100mVpp, 1Vpp and other different step values, the maximum amplitude range 1mVpp~20Vpp step-less adjustment .

11, the frequency range is wider, the maximum frequency range of sine wave is 1uHz~60MHz, the maximum square square wave is 1uHz~25MHz, other wave frequency range is 1uHz~20MHz, the full range of frequency resolution is 1uHz, the whole range of frequency is not divided, direct digital setting.

12. The rising edge time within the square wave 5V is as low as 7nS, and the maximum output frequency can reach 25MHz.

13, more abundant waveform types, the instrument not only presets 33 kinds of common waveforms for the user, but also provides users with up to 64 groups (8192 * 14-bit) of user-defined waveform storage space, the user can use the host computer provided by our company Software editor download; it is worth mentioning that our pulse wave pulse width not only supports the duty cycle adjustment method, but also supports the pulse width to be accurately set between 20nS-1S (our competitor's products mimicking our interface do not have this adjustment method). The instrument output waveform totals 97 groups.

14, powerful scanning function, the instrument not only supports the internal parameter settings on the signal frequency, amplitude, duty cycle, bias level parameters of the scan, but also supports the external analog voltage on the instrument output frequency, amplitude, duty cycle, bias Level modulation;

15, more comprehensive measurement function, the instrument can measure the signal frequency, period, positive pulse width, negative pulse width and duty cycle, and all parameters are displayed in the same interface, do not need to flip back and forth view; counter function has DC And AC two kinds of coupling methods, effectively solving the problem of inaccurate AC coupling count. The maximum measurement frequency of the instrument can reach 100MHz, and the minimum measurement frequency is 0.01Hz.

















Ramp, Triangle















Arbitrary Waveform





Minimum pulse width 20ns (All models of pulse wave minimum width can  reach 20ns)

Min. Resolution on all frequency ranges
1μHz (Min.  resolution can reach 1μHz on all frequency range to ensure adjusting accuracy  under high frequency. For example, it can output 10.000000000001MHz signal).

Accuracy ±20ppm

Stability ±1ppm/ 3hours

Waveform   Characteristics

Sine, Square (Duty Cycle adjustable), Pulse (Pulse width and cycle time  can be set accurately), Triangle/Ramp, Sawtooth   Wave, CMOS, Four channels TTL, DC, Half wave, Full wave, Positive Step,   Inverse Step, Positive Exponent, Inverse Exponent, Lorenz Pulse, Multitone,   Noise, ECG, Trapezoidal Pulse, Sinc Pulse, Narrow Pulse, Gauss White Noise,   AM, FM, and other 64 sets customer-defined waveform.

Non-Volatile Storage Can store 64 user-defined arbitrary waveforms, (8K 14bits) * 64

Waveform Length 8192 points * 14bits

Sampling Rate 250MSa/s

Vertical Resolution 14 bits


Harmonic Suppression
≥50dBc(<1MHz);   ≥45dBc(1MHz~20MHz);

Total Harmonic Distortion <0.5%   (20Hz~20kHz,0dBm)


Rise/Fall Time ≤7ns (VPP<5V)

Overshoot ≤5%

Duty Cycle 0.01%~99.99%   (Resolution 0.01%)

Sawtooth wave

Linearity >99%   (0.01Hz~10kHz)

Output   characteristics

Frequency≤10MHz:   1mVpp~20Vpp;
10MHz<Frequency≤20MHz:   1mVpp~10Vpp;
Frequency>20MHz:   1mVpp~5Vpp;

Resolution 1mV

Amplitude Stability ±0.5%/   5 Hours

Amplitude flatness ±2.5%(<10MHz);±5%(>10MHz);

Waveform Output

Impedance 50Ω±10%(Typical)

All channels can work more than 60 seconds   when the load is short-circuited.

DC Offset

Offset  Range Frequency≤20MHz:   ±10V;  Frequency>20MHz: ±2.5V;

Offset Resolution 1mV

Phase Feature

Phase   range 0~359.99°

Phase resolution 0.01°

TTL Output

TTL Level  Amplitude >3Vpp

Fan-out >8 TTL LOAD

Rise/Fall Time ≤10ns

CMOS Output

Low-Level <0.3V High-Level 1V~10V

Rise/Fall Time ≤18ns

External Measurement

Frequency, Period, Positive/Negative Pulse Width, Duty Cycle

Input Voltage Range 1Vpp~20Vpp

Frequency Meter

Resolution 0.01Hz (Gate Time = 100S)

Range 0.01Hz~100MHz

Sensitivity Gate Time 3   grades (1S, 10S, 100S) adjustable


Range 0-4294967295

Coupling DC, AC

Working Mode Manual


Measurement Range 5ns ~ 20s

DC coupling measurement Pulse Width

Measurement Range 0ns ~ 20s

Resolution 5ns

Duty Cycle

Range (Display) 0% ~ 100%


Carrier Waveform Sine, Square, Ramp, Arbitrary (except DC)

Sweep Type Linear or Logarithmic

Sweep Direction Up, Down and round trip sweep directions;

Sweep Objects Frequency,  Amplitude, Offset, Duty Cycle

Sweep Time 0.01S~999.99S/Step

Setting range Starting position and Finishing position can be set arbitrarily.

Sweep Range Decided by Parameters setting.

VCO  (Voltage Control Output)

Modulation signal range to input 0~5V

VCO signal frequency range 0-1000Hz

VCO control object voltage controlling frequency (VCF), voltage controlling amplitude  (VCA), voltage controlling offset, voltage controlling duty cycle.

VCO special function Can Amplitude Modulate (AM) or Frequency Modulate (FM) by external analog   signal.


Modulation Type AM, FM, PM, ASK, FSK, PSK

Carrier Waveform Sine, Square, Triangle, Ramp, Arbitrary waveform (Except DC)


Source Internal (CH2) / External (VCO IN Port)

Modulating Waveform Sine, Square, Triangle, Ramp, Arbitrary waveform

Depth 0% to 100%

Modulating Frequency Internal: 1μHz~1MHz;  External:   1μHz~2KHz;


Source Internal (CH2) / External (VCO IN Port)

Modulating Waveform Sine, Square, Triangle, Ramp, Arbitrary waveform

Modulating Frequency Internal: 1μHz~1MHz;  External:   1μHz~2KHz;


Source Internal (CH2) / External (VCO IN Port)

Modulating Waveform Sine, Square, Triangle, Ramp, Arbitrary waveform

Phase Deviation 0° to 360°

Modulating Frequency Internal: 1μHz~1MHz;  External:   1μHz~2KHz;


Source Internal (CH2), External (ASK IN Port), Manual

Modulating Waveform Square with 50% duty cycle.

Key Frequency 1μHz~10MHz


Source Internal (CH2), External (FSK IN Port), Manual

Modulating Waveform Square with 50% duty cycle.

Key Frequency 1μHz~10MHz


Source Internal (CH2), External (PSK IN Port), Manual

Modulating Waveform Square with 50% duty cycle.

Key Frequency 1μHz~10MHz

Burst  Function

Carrier Waveform Sine,   Square, Ramp, Arbitrary (except DC)

Burst Count 1~1048575

Trigger Source Manual, Internal, External (AC/DC)

General Specifications


Type 2.4 inch, TFT Color Display.

Save & Load

Amount 20

Position 01 to 20 (01 for start default value)


Type USB to Serial interface

Protocol Command line mode, providing communication   protocols.

Communicating Speed 115200bps (Industrial standard)


Voltage Range AC100V~240V

Technical SMD, LSI, Reliable and durable

Buzzer Can be turned on/off by setting.

Operation Buttons and knob continuously.

Environment Temp.: 0~40℃, Humidity: ﹤80%

Size 200mm * 190mm *   90mm (L * W * H)

Weight 900g

Package Size 25cm * 21cm *   10cm (L * W * H)

Package Weight 1kg (Main unit, accessories and packing materials)

Inside the Unit

I’ve already had a request to check earth voltage (60vAC according to my sensitive UNI-T meter) and I’ve been asked to take a look inside. Turns out that was harder than it might seem. 4 screws to pull out but then more tiny screws inside hold the top and bottom together via the front panel so please be kind re: photos below. My reservations about a smell do not appear to be born out in any discolouration of the power supply board. I did not that the ground line is nothing more than a signal line however. Here are the pics.


Above, the board at front (taken from a partly open back) is the power supply. Below, the logic board. You see here the connectors on the PSU and the logic board, including the unremarkable earth wire in the middle.


Simple testing

A simple, single-channel 1.5Khz square wave audio test was easy and went well. Having the unit power up automatically on plugging in is good for PCs but I’m not sure it would have been my choice for test kit, but that’s a minor gripe.

Single channel audio test

That’s it for now.


15 thoughts on “FY6800 Signal Generator

  1. Can you measure ac voltage from bnc connector to earth ground?
    Can you make a foto of the inside please especially the psu?

    1. Interesting... according to my accurate, high impedance meter on AC volts, 62v ac - when I get a few minutes I'll check what current would pass. Not a lot I suspect, but worth checking.

      1. That's because of the Y-Capacitor in the SMPSU. I hoped they learn and include a linear CPU so that there is no phantom voltage to earth ground that could kill sensitiv electronics. If you do a lowZ measurement the voltage should be about 0V.

        From the pictures the inside looks pretty much similar to the FY6600. So they changed the frontend what is very fine (copied from the JD6600) but they missed the chance to make a complete new product that solves the "issues" from the FY6600 what I hoped they do.

        Do you know if the fimrware is upgradeable? That would be a really useful upgrade looking on the problems they had with the FY6600 firmware.

      1. One of the two middle cable of the connector from the smpsu to the mainboard is connected to earth ground? So they connected the pcbs' ground to earth ground.
        With this you shouldn't measure such a high phantom ac voltage from the BNC connector to earth ground. Very suspicious because this was the easy solution for the FY6600 owners to get rid of this problem. The better solution is to replace the smpsu with a linear psu.

        What I can see from the main pcb looks very similiar to the FY6600. I would really appreciate if you could make some more good daylight pictures.

  2. I love my signal generator. First time I've had my own to use and it has been great for things like PWM testing, it also has a DC output for ADC testing etc. The waveforms are also great for testing amplifiers and I used the sine wave recently to test an audio comms design to find a small design issue. It saved me days of work. If you do any kind of analog design, these are well worth to have on your test bench.

  3. Interesting. I have a modest function generator which I never use. I also have a hideously expensive HP arbitrary waveform generator, this is so complex to use that I ended up building my own hardware to do what I wanted.
    I think I'm with Dave. I don't do much analogue work nowadays but get it.
    Decent instruments are SO affordable nowadays! 🙂

  4. Hey Mr.Peter. I've just pre-ordered the FY6800 from banggood, Just to be clear here, did they fix the ghost voltage between the BNC and Ground as they advertised or not?
    Also, I would be really thankful if you could tell us what firmware version is it running on?

    1. version 1.6 in my case. I mentioned I did a quick meter test and there did appear to be 60v between bnc and ground.. If this is a fix the company promised (and not just a fluke of my meter reading) please do point me in the right direction of any conversation on the subject.

      1. Many thanks Mr.Pete for your fast reply,
        Regarding the grounding issue, their Fy6800's preorder's page , in the "Features" part of the product description, you will notice that they've typed (in red color) "Standard 3-pin power plug adds ground protection" which means they've implemented a ground line and using some natural common sense this would definitely mean that the BNCs must be grounded, or what else can be? Please correct me if I'm wrong though.

        This is the link:

        1. On the front you can see that the BNC connectors should be grounded. So with a dmm in continuity mode you should measure about 0Ohms to ground pin on the mains connector to check this.
          Removing the phantom voltage by grounding the BNC connectors is a cheap but IMO not the best solution. Replacing the SMPSU by a linear PSU would be the much better solution but more expensive.
          So the only left advantage for the FY6800 over the FY6600 seemes to be the much better front panel but technically it looks as if FeelTech did not want to bring a technically better product to their customers. I am pretty sure they did not implement firmware updates over usb connector.

          It's a pitty.

            1. I am only talking about the 6800 being the successor to the 6600.

              FeelTech was in talk with people on the EEVblog and they got very much and good feedback what a good successor could be like. Now it looks as if the only thing they made is a better front panel to compete in this discipline with RDs' JDS6600. And that's a pitty. From my point of view they missed the chance to make the best low cost function generator on the market. I can be wrong and they may changed the hardware quality but what I can see from your pictures the hardware is more ore less identical to the FY6600.

              I like the FY6600 but I think the FY6800 missed two important things that may not be important enough for the mass.

              The JDS6600 for example uses an external 5V/2A SMPSU, so it is very easy to replace this SMPSU by a linear one without any modification to the unit itself and you get totally rid of the phantom voltage problem while still having floating ground what can be very important.

              The JDS6600 has less functionality but somewhat better signal quality (even it is only 12bit). I compared the JDS6600 and FY6600 at 50 Ohm outputs and the JDS6600 is doing better output adaption but the FY6600 is better in higher frequencies in the double digit MHz area. I hope to see comparisons with the FY6800 soon. I am sure there will be soon in the EEVblog.

              To be clear, I like the FeelTech products. You don't get a better only mostly similar products for the price.

              I own a FY6600 that I modified (linear PSU inside and replaced the output amps and TCXO) and I own an unmodified JDS6600. Today I would get a FY6800 if I would not already have. But I'm a little disapointed that FeelTech did not make a successor to the FY6600 that removes all the main problems (PSU, flashable firmware and better front panel user interface). They missed the chance.

  5. I totally agree with you Pete. For the price tag (of about 119 - 120 USD) and all these features It totally worths it! As a hobbiest I pre-ordered one and It will be my first ever signal generator! I definitely wouldn't need any SUPER DUPER HIGH QUALITY MULTIPLE FUNCTIONS signal generator after all, If so I wouldn't call myself a hobbiest, would I?

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