This is all well known, but did you notice that (with proper termination of course) the generator's output declines from 10-60 MHz by about half (-6dBv)? I am talking about the FY6800 actually and want to use it as VCO expecting a flat response. I didn't go inside yet to measure directly at the DAC but I suspect there is something fishy going on at the amplifiers. Has this topic been discussed here or anywhere? Is there a "hack" available to fix this?
Thanks in advance
Lutz
I don't understand what you're showing.
Is the sweep synchronized with the scope trigger?
Also please take a look at the PCB. Is there any flux residue visible? Flux absorbs moisture out of the air. This results in an environmentally dependent parasitic capacitance. It would not take much capacitance to cause the drop in output you're seeing.
If you see any flux, clean it off with isopropyl alcohol and an old toothbrush and retest. I've done quite a few repairs, including an HP 34401A which had been repaired previously that consisted of nothing but cleaning flux residue off the board. The 34401A was completely non-functional until I cleaned it. But after cleaning meets the factory spec. It's the more accurate of my two 34401As. The other one was a closet queen and saw very little use.
Have Fun!
Reg
I supose you have another generator that is linear as you want , otherwise you don't know where the problem is .
I have v3.1 , the firmware will work ?Yes it will. I tested it with flash eeproms v3.1 and V3.2.
It doesn't work with a V3.3 eeprom but as I don't have a V3.3 front panel, I can't see what changed in the FP-FPGA protocol for v3.3.
I have v3.1 , the firmware will work ?Yes it will. I tested it with flash eeproms v3.1 and V3.2.
It doesn't work with a V3.3 eeprom but as I don't have a V3.3 front panel, I can't see what changed in the FP-FPGA protocol for v3.3.
Hello , I flashed a spare microcontroller with your firmware ... quick bug , in sinewave the output is badly distorted if I go up in frequency up to 197KHz . If I go back down from here is OK untill 1KHz or something when the distortion appears again . Something in comunication with the FPGA is not quite right .
Hi Fremen67 and welcome back! I surely hope that you were just busy and nothing tragic happened.
How may I help to figure out V3.3 and what do I need? My FY6600 is V3.3. I don't have a logic analyzer but I do have a Rigol DS1054Z. Probably not enough, eh?
It would be really nice to see FOSS code that would allow other Chinese OEMs to clone the F***Techs and improve them. It could not happen to a more deserving company.
Can anybody post a csv file that is accepted by FT software, or fremen's software? I can't figure out the format. I'm trying to do a simple ASK modulation on CH1 from CH2 and anything I try will just return an error message and shut down the program.
Thanks,
Miti
Just a sugestion , the frequency displayed is still hard to follow with just one decimal point when it is in MHz range for example ... I have to count allways how many digits are before the dot . Would be nice to display MHz , KHz and to move the point accordingly .
The sub-hertz many many digits I think shouldn't be displayed when are not used ( set to 0 ) .
If you go to the max with the tens of MHz digit ( by error or not ) , the rest of the display goes to max also and you lose what you have set , maybe you want 59.123456MHz . I think would be better not to let you go beyond 5 if 6 and the rest of the digits would be an invalid frequency .
When you go down in frequency the same thing happens if you reach 0 and turn the encoder one more time , the rest of the digits are erased to zero , I don't think this is desirable . Zeroing the display could be usefull , but with a long press on the encoder or another combination when you are in frequency adjustment .
I noticed I needed a version of the original Feeltech software installed on the machine before Fremens would run ,I had been trying out the latest FY6900 version pc software ,maybe this caused the issues I am seeing , I wonder is there a particular version of the Feeltech pc software I should be using for maximum compatibillity to Fremen's FP code ,
I did have another think about the double button press being required to select channel and mute/unmute , maybe a nice idea would be when you initially depress the channel 1 or 2 button have it select that channel to top if its not there already ,then let the unlatching of the button send the command to mute or unmute as required , now only a single press (and release) covers both functions , it only logical captain Fremen