Mine is version 3.0. Thanks for the warning about doing a factory reset.
The array of modifications various posters have come up with to improve the FY6600 is interesting and depends a lot on what that particular user’s main requirements are. My first interest was mainly to make the FY6600 safer by including a real ground through a 3-wire power cord and not to rely on an iffy virtual ground. Secondly I really wanted to make the timebase more stable and a LOT more accurate with the option of using an external 10 Mhz reference from GPS or a rubidium source. Along the way I discovered the existing power supply was crappy and not what I considered fixable so that had to be replaced as well. The grounding and timebase modifications I made worked as well as I hoped they would so that left the power supply and possibly the output amp that others considered lacking.
Recently I tried replacing the output amps as others had recommended and didn’t see that really improved anything for me and went back to the original single chip. I rarely go above 5 volts output so this modification wasn’t that high on my to-do list. Others have run the FY6600 main board on +/-15 to improve the output at higher levels with no reported problems but I was still worried about a possible failure. I had tried a +/-15 vdc supply I modified to put out about 14.2 vdc to perhaps give me a little more margin of safety. I was uneasy in running the main board at a full 15 volts with the caps on the board rated at 16 volts (as others have mentioned) plus I wasn’t so sure that some of the other parts wouldn’t be stressed by the higher voltage. Almost all SMPSs have one adjustment for the +5 and the other two supplies are ratios of that so to just use that adjustment to lower the +/-15 supplies to about 14.2 volts, which I thought might be safer, would mean that the +5 would be lowered as well by about .3 volts, and I didn’t find this acceptable. What I tried was to put a conventional 3-amp diode in series with the two + and – supplies which would drop those voltages by about .8 to .9 volts while leaving the +5 right on.
While that worked to lower the +/- voltages a little and made me feel a little better, the supply I used that just fit in the space in the case was a supply capable of supplying 60 watts. This meant that although the main board doesn’t require much power, the supply used 10 watts and most of that was given up as heat and the FY6600 ran warmer than I liked. The first 40 watt +/-12 vdc supply I tried was a little more efficient but still generated some heat and used about 8 watts. The supply I settled on was a 25 watt +/-12 vdc supply I have shown previously that uses only 6 watts when powering the FY6600 and 4-5 watts when the front switch is turned off but parts of the main board are still powered. Keep in mind that the OCXO that I used as a timebase stays powered when the back switch is on and does use about 1.5-1.8 watts when it is at temperature but that doesn’t contribute much internal heat.
Here are 2 photos. One shows how I added the diodes in series with the +/- supply lines and bypassed then with a couple of tantalum capacitors if anyone might want to try that. The second photo is of the 25 watt supply I showed before. I’m pretty sure these are all the modifications I’ll be making to the FY6600 but I’ll keep reading to see what other great ideas others come up with. In a way I spent more time with the FY6600 apart than with it together and doing what amounts to trying to make a Ford run like a Mercedes when I might have been better off buying the Mercedes in the first place!
It would be very interesting to know who the designers are.
Its one.
Though it is always possible they changed it to two on later builds / firmware's especially with all these links to Frauenhofer around.
Hi!
My plan to buy one to document on this Forum has borne fruit and I'm expecting delivery after the Christmas Holidays!
I'll be posting pictures, details of FW version, waveform samples, plus circuit-details, parts lists, etc., rev'd from the unit exactly from as I receive it, and I'll report the effect of the OEM's "Factory Reset" - if it borks the unit then I'll send the STM32 FP Assembly to Member DC1MC for his perusal!
Unfortunately I haven't got (can't afford yet!) one of those nice colour-screen LED Oscilloscopes that other members publish their oscillograms from, I can only offer ordinary analogue 'scope trace pics for now!
Chris WIlliams
I just used a cheap and cheerful Chinese switched one https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235
Staying IEC made sense as most other things on my bench already have them. A little off topic but I also got a couple of these which tidied up my bench and gear shelf a lot. https://www.ebay.com.au/itm/Black-57cm-IEC-320-C14-Male-to-3-x-C13-Female-Y-Splitter-Power-Cable-Cord/331700358437?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
...but checking the output of the FY6600 after it has done all its magic to produce this frequency and waveform...
What about these guys. they are cheap cheerful AND filtered ?