6700 GPS DO

Raul Pla

I have 2 6600 GPSDO, and have come across a 6700 at an affordable price to buy. Im considering it (and sell a 6600) because a local ham told me Flex ended the 6700 because it became too expensive to produce and at the cost of production, it would not be sellable to hams. So, does the 6700 possess some performance better than a 6600? perhaps the architecture or processors?

I skipped the 6700 before because I would never use 8 slices. The 144Mhz is a plus though. I am adding transverters all the way to 10GHz and feed a PGXL and TGXL. I've become a Flex aficionado because it's a wonderful system.

Is the 6700 better in ways besides the 144 MHz and the extra 4 slices?

Thanks for your time, W4AWI Raul

Russ Ravella

Hi Raul,

I went from a 6600 to a 6700 a few years ago. Besides the 8-slices and 144mHz capability there's no significant difference in performance that I'm aware of.

However, there are some differences in its configurability. I don't remember the details so I won't take a chance on misleading you by guessing here but you can easily see them if you look at their respective manuals. The 6700 has "loop" path abilities the 6600 doesn't for example.

The reason I went to the 6700 is I'd had very serious reliability problems with three 6600s to that point, each having to eventually be replaced, and when Flex told me they were going to have to replace it again I asked if the 6700 was more reliable. They said it probably was because it's primarily built on a single board while the newer form factor in the 64/6600s involved more internal connectors which were contributing to their reliability issues.

So for that reason alone I went to the 6700 from there. That one also had to be replaced within a couple of months. But by that time, they had started manufacturing them in-house and I got the first 6700 so manufactured. I've never had any problems with it until just now when screwy things started happening after the v3.9 update which are still being diagnosed.

So all of that in the "for what it's worth" category. Whatever you decide, I hope it works out great for you ! By the way, I felt the same way as you about the additional 4 slices. I just wanted the potential improvement in reliability. However, I became hooked on them within a few hours and can't live without them now. In fact, I'm not planning to upgrade to an 8XXX until/unless they come out with an 8-slice version because for me it would be a significant downgrade. Again, FWIW …

73 Russ KR6W

Raul Pla

Thanks Russ! Very good info for thought indeed. I had barely started using the 6600 a few months then took the shack apart for construction. It is a 2019 model and it came from a good home, so I bet he had it serviced, I have had no issues. My latest one is a 2021 model still in the box, and it looks like it got serviced too, per the box markings.

Im inclined to buy the 2018 6700 I found if it was the one with the board made in-house. I better get the serial number and ask Flex. If I take too long on all this I think it will get soled to someone else. It was just at Flex for updates and fans.

Reading the forums I found some concern about future availability of parts, either very expensive or not available at all..

You might be right about all the slices, I guess I would need at lest 2 antennas up, and the 2x8 Antenna Genius too. Lots to play with.

73, W4AWI Raul

Russ Ravella

Hi Raul,

Great, glad it was helpful. I just looked up when I received the second 6700 (first built in Austin) and it was 9/24/20 in case that's of some help.

One more comment in case it's helpful here or elsewhere - I mentioned I'm having an issue with the .9 update which is being diagnosed. Since I said that, Flex has had me replace the SD card and that didn't help. But it occurred to me the issue (radio crashes) seems to be centered around TGXL operation and at this point I'm about 75% convinced it's the new TGXL ..17 f/w or the TGXL integration part of the SSDR .9 update that's causing it. Not the radio.

Anyway GL with whatever you end up doing and have a great week !

73 Russ KR6W