FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator - Page 1
Forum section: electronics / testgear

author: Amysmith
author_rank: Newbie
timestamp: July 28, 2017, 05:16:02 am
content: I looking very cheap FY6600 arbitrary waveform signal generator on ebay, the sine wave support 30Mhz, 50MHz, 60MHz on different models, and arbitrary waveform to 10MHz.with voltage control output function.http://www.ebay.com/itm/FeelTech-FY6600-2-CH-DDS-Function-Arbitrary-Waveform-Pulse-Signal-Generator-VCO-/263105160109?Only 90.79 USD for 30HMz, so I'm thinking buying one.Does anybody on this forum have experience with the FeelTech FY6600 function generator?Who has bought this FY6600?How accurate and reliable is it?I will grateful for any suggestion from all.

author: nctnico
author_rank: Super Contributor
timestamp: July 28, 2017, 08:37:20 am
content: I guess this is a beefed up version of the older models. The price is pretty sweet though for a 60MHz function generator! I'm wondering what the TTL outputs can be used for. Digital pattern generation would be nice.

author: don.r
author_rank: Frequent Contributor
timestamp: August 05, 2017, 01:42:36 am
content: Interesting unit. I see that, apart from the upper limit of the sine wave output, there appears to be no functional difference between the 30MHz unit and the 60MHz one (25MHz square wave and 10MHz for all others). Has AM/FM/ASK/PSK/FSK/VCO and AWG capability. Would be nice to see a comparison of this with the JDS unit.My old analog Wavetek does AWG... you just have to hit it hard enough. Time for a new unit, I think.PS: Here is the FY6600 Manual, in case anyone is interested:http://kenswu.zzvps.com/Function/Manual/FY6600%20Series%20Users%20Manual%20V2.2.pdf

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 05, 2017, 07:22:58 pm
content: Has anyone checked what voltage(s) the internal power supply provides to the rest of the system? I am fairly interested in this model, but I have issues with using Chinese budget power supplies on mains. I am just not comfortable with that. Maybe that upgrading the power supply to something trustworthy could soothe my worries.If there is no easy way to upgrade the power supply, I might order the competing JDS6600 instead. That uses a 5V plug-pack that is easily swapped for a trustworthy supply.

author: MadTux
author_rank: Frequent Contributor
timestamp: August 05, 2017, 08:01:53 pm
content: There is already a teardown available on youtube:https://youtu.be/LNBX3yrp5ps?t=1m43sTest from the same guy:IMO just the classic chinese plastic box with a minimal amount of electronics inside.

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 05, 2017, 10:10:45 pm
content: Quote from: Mr. Scram on August 05, 2017, 07:22:58 pmI just noticed the mechanical switch on the back. The option to switch the unit off properly changes the proposition a little bit, as you can actually turn the supply completely off when you are not around. However, I would still rather see a plug-pack powered device.

author: don.r
author_rank: Frequent Contributor
timestamp: August 06, 2017, 12:06:51 am
content: Quote from: Mr. Scram on August 05, 2017, 07:22:58 pmGoing by the teardown video, the PSU looks reasonable and fairly straightforward if you want to replace with your own. Its on its own separate board with lots of extra internal space. Looks like two, maybe three, different output voltages.EDIT: Looking at the video its 6 lines, 2 X 5V, 2 X GND, 2 X 12V.

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 06, 2017, 01:59:16 am
content: Quote from: don.r on August 06, 2017, 12:06:51 amGood eye. I looked for markings on the main board, but missed the voltages on the power board.Those are very convenient voltages. There are plenty of power supplies available with those, including ATX and other PC power supplies. The trick is to find one that fits neatly into that box.

author: don.r
author_rank: Frequent Contributor
timestamp: August 06, 2017, 03:30:04 am
content: Quote from: Mr. Scram on August 06, 2017, 01:59:16 amIts only my speculation from what I could see on the video. I'll probably order one sooner rather than later and can post up a review... when it arrives.

author: StillTrying
author_rank: Super Contributor
timestamp: August 06, 2017, 11:44:32 am
content: Is it just me that thinks 00'010.000'000'000KHz is a horrible way to show 10kHz. Does it need to be shown to 1 millionth of a Hz ?

author: Specmaster
author_rank: Super Contributor
timestamp: August 06, 2017, 01:03:57 pm
content: If you hang a while, there will more then likely be another similar unit launched by another company in China (Minghe) that will do away the SMPS and its associated possibility of high voltages on the ground of the BNC and USB sockets by using a 5VDC wall wart to feed the unit. Its smaller less powerful cousin 20Mhz or 25Mhz has been tested and people have noticed tingles when using them. I have a Minghe MHS-5200A that uses the 5vdc wall wart, no problems with that at all.

author: Specmaster
author_rank: Super Contributor
timestamp: August 06, 2017, 01:16:14 pm
content: It seems that there is another unit already on Ebay that goes upto 40Mhz but with a wall wart, here's the linkhttp://www.ebay.co.uk/itm/24-25-30-40MHz-Dual-channel-DDS-Arbitrary-Waveform-Function-Signal-Generator-Kit/172775654978?_trksid=p2481888.c100651.m4497&_trkparms=aid%3D777001%26algo%3DDISCO.FEED%26ao%3D1%26asc%3D20160801204525%26meid%3D87253c69a4d8403598de045c372b2e6f%26pid%3D100651%26rk%3D1%26rkt%3D1%26&_trkparms=pageci%253Aa06cd29b-7aa8-11e7-afd3-74dbd180fb11%257Cparentrq%253Ab7ab21da15d0aa48d8bc3de8fffcbe6c%257Ciid%253A2

author: don.r
author_rank: Frequent Contributor
timestamp: August 06, 2017, 02:33:22 pm
content: Quote from: Specmaster on August 06, 2017, 01:03:57 pmThat's the JDS6600 which has the wall wart, already a thread or two on it in the forum. It appears to be 12 bit rather than 14 and have no modulation capabilities. The internal PSU on the FY6600 seems to have changed a little from the ones used in the FY3224S with at least the inclusion of an X-class cap. But its probably the crappy xformer leaking the AC onto the ground. I like the physical buttons on the JDS.

author: nctnico
author_rank: Super Contributor
timestamp: August 06, 2017, 04:01:02 pm
content: Quote from: Specmaster on August 06, 2017, 01:03:57 pmMost wall-warts have capacitors connected to mains which results in half the mains voltage at the output so that isn't a solution. The best is to fit a ground outlet in the function generator.

author: Specmaster
author_rank: Super Contributor
timestamp: August 06, 2017, 06:07:43 pm
content: you also of course have the option of powering it from a battery pack if required.

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 06, 2017, 09:15:59 pm
content: Quote from: nctnico on August 06, 2017, 04:01:02 pmThis is where my lack of experience shows. You say a wall wart is not an adequate solution?What would be needed to hook it up correctly and how would one go about it? Replacing the two prong socket and switch with a three prong fused socket should be doable. I know ground often is hooked up to the case or chassis of the device, but this case is plastic. How would you then hook the ground up internally? Is it as simple as connecting internal ground to the ground pin, so that the fuse box in your house can detect any difference between incoming and outgoing power?Quote from: don.r on August 06, 2017, 02:33:22 pmModulation is also what interests me about the Feeltech. I currently have no use for it, but if history is any indication, I will as soon as I purchase the device without it

author: Specmaster
author_rank: Super Contributor
timestamp: August 07, 2017, 12:01:58 am
content: Like Nitco said most cheap and certainly the supplied wall wart with the unit I suspect will have the capacitor but you can get better ones that are multi-voltage out ones that normally have a linear power supply, they will be larger and heavier and considerably more expensive but should well worth it for the piece of mind alone.

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 07, 2017, 12:16:27 am
content: Quote from: Specmaster on August 07, 2017, 12:01:58 amI thought he didn't consider it to be a solution because a wall wart leaves the device floating. Guess I was wrong

author: cdev
author_rank: Super Contributor
timestamp: August 07, 2017, 03:39:14 am
content: Although everybody is alluding to it, for the benefit of newer visitors, let me just recap why everybody is talking about the power supply. If you are just reading about them for the first time, the crucial unvarnished fact is that unmodified, the "ground" connection on the BNCs on the older FY32xx carry leakage voltages high enough not only to damage delicate components many times over, but also to present a shock hazard if somebody is sweaty or has wet hands, under some conditions.But the big danger it presents is to chips, if its used ungrounded, which is fairly likely given its target market, electronics hobbyists.So one has to be careful to always ground it - and perhaps even unplug it when it isn't in use.How much more would it have cost them to do that right?

author: don.r
author_rank: Frequent Contributor
timestamp: August 07, 2017, 03:51:46 am
content: Quote from: cdev on August 07, 2017, 03:39:14 amTo be fair its a tough call. Sometimes you want a floating source. Linear supplies are more expensive and heavier (important when shipping from PRC). Something has to give at these prices.The USB port could always be connected to a grounded source like a PC. The other thing you could do is add another Y class cap from the secondary negative to an external ground source and redirect the primary Y to this ground as well. Internal ground still floats and is isolated but AC has a path to PE.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 07, 2017, 05:15:45 pm
content: The leakage current problem is not so much about an internal or external (wall wart) power supply. It is more about switched mode power supply not using PE or a classical transformer. To meet EMI regulations a SMPS essentially needs the class y capacitor from the output to an RF ground. With a class II supply (using only 2 wires) there are usually 2 Y capacitors towards both sides of the supply and thus half the mains voltage when measured with a high impedance meter. This applies to the cheap internal supply and most SMPS based wall warts. Most instruments should survive the small voltage spikes of the 5 nF (or so) Y cap.A way around this would be using a supply with a classical transformer or a SMPS with a third wire (PE). The PE connection could be used for a direct connection the GND (e.g. BNC) or just for the y capacitor. So ideally they would have 2 class Y caps from the power pin to warts a PE connection and then a 3rd y cap (and maybe a resistor in the M Ohms range) to the output.

author: don.r
author_rank: Frequent Contributor
timestamp: August 07, 2017, 05:50:04 pm
content: Quote from: Kleinstein on August 07, 2017, 05:15:45 pmYes. This was my thought. A simple "fix" would be to change the power connector to an IEC and then add a Y cap (and maybe a high value resistor) from internal ground to PE. That should droip the leakage to very low levels. And if you don't need a floating output, just short the internal ground to PE.

author: Mr. Scram
author_rank: Super Contributor
timestamp: August 07, 2017, 06:07:32 pm
content: Quote from: Kleinstein on August 07, 2017, 05:15:45 pmI found this power supply. Even though it is obviously switching and cheap, it does have a third prong and does come from a reputable source. I was suprised the shipping does not kill it either.https://www.sparkfun.com/products/11296Quote from: metrologist on August 07, 2017, 05:58:25 pmI am curious about the differences between the versions too and whether they are actually different, or just firmware limited.Dave seems to be quite harsh on anything cheap and Chinese, so I do not expect a recommendation from him.

author: don.r
author_rank: Frequent Contributor
timestamp: August 07, 2017, 06:14:42 pm
content: Quote from: Mr. Scram on August 07, 2017, 06:07:32 pmOne of the 12V lines might be negative like on the FY3200 series. Best get someone to confirm before ordering parts. Yeah, I don't expect any review from Dave. He concentrates on either the professional stuff or the "serious" home lab and I expect he would recommend a used unit of known quality before this one. Problem is that even the cheapest AWG's from brand names go for twice the price or more used and much more if you want more than 25MHz. I am looking to use the unit in a space limited setup as well and this is one of the smaller ones.As for the differences, in the manual I can only see the sine wave output as being different between the models. Everything else looks the same. Probably a firmware hack but then its only about $30 difference between the 15MHz and the 60MHz so hardly worth the time.

author: don.r
author_rank: Frequent Contributor
timestamp: August 07, 2017, 07:58:33 pm
content: Quote from: metrologist on August 07, 2017, 07:56:19 pmSame resolution of 1uHz across the board. The only other limitation is the 15MHz unit is restricted to a 15Mhz square as well as sine wave. I think the 30 or 50MHz units are the best value.