Flex 6500 v Flex 6600

  • 2
  • Question
  • Updated 2 years ago
Is there anyplace I can see a side by side comparison between the Flex 6500 and the new Flex 6600 (non-M version)?

The only reason I'm looking is because I have long wanted the ability of RX A and RX B as well as XVTR A and XVTR B and be able to set two slices one for 70cm (transverter) and one for 2m (transverter) and have the ability to transmit and/or receive on either without switches... and from what I am seeing the 6600 has that ability (well it has the ports)

The other thing I'd like to see is any other differences between the two Radio's.


Photo of David Warnberg

David Warnberg

  • 698 Posts
  • 91 Reply Likes

Posted 2 years ago

  • 2
Photo of Tim - W4TME

Tim - W4TME, Customer Experience Manager

  • 9198 Posts
  • 3558 Reply Likes
1.) The 6600 is expected to have slightly better receiver performance.  It hasn't been measured so I do not have any hard numbers to share.

2.) The 6600 will have 2 SCUs for diversity reception and for using multiple antennas at the same time.  This add RX-B to the 6600.

3.) The 6600 will have higher rejection out of band preselectors (7th order vs 3rd order filters) for the contest bands

4.) The 6600 will have 2 XVTR ports

5.) The 6600 costs less than a 6500
Photo of KY6LA - Howard

KY6LA - Howard, Elmer

  • 3784 Posts
  • 1637 Reply Likes

Depends if you want to use multiple antennas at the same time on same or different bands.

If so, then the 6600 with 2SCU's wins hands down because it gives you full duplex and diversity capability. 

Photo of Ken - NM9P

Ken - NM9P

  • 4239 Posts
  • 1351 Reply Likes
FrankP, I own a 6500 and had put a deposit on a trade-up to a 6600, but some things have changed in my world which will delay that about a year....

Which you choose will depend upon what you want to do with the rig.

If you want to do SO2R contesting with the same rig,

or if you would like to monitor widely divergent bands at the same time - like 6 & 160, or 80 & 10,

or if you would benefit from 7th order bandpass filters on the rig,

or if you want to do diversity reception, using two different antennas on the same band to reduce noise...

Then you will want to spend the extra for the 6600.

If NONE of that interests you, then you will still be blown away by the 6500!  It is STILL one of the best rigs available, even though it is discontinued!

Ken - NM9P
Photo of FrankP


  • 25 Posts
  • 5 Reply Likes
Thanks guys!
Photo of Ria - N2RJ

Ria - N2RJ, Elmer

  • 2314 Posts
  • 956 Reply Likes
If you're doing SO2R in a single radio you need the 6600 (or 6700).

Photo of Ken - NM9P

Ken - NM9P

  • 4239 Posts
  • 1351 Reply Likes
I forgot to add the ability to have two transverters connected and operating at the same time - I.e. 2 Meters and 70 cm full duplex for contesting or satellite operation!
Photo of KF4HR


  • 827 Posts
  • 274 Reply Likes
Tim - does the 6400/6600 units utilize a upgradeable module design, similar to what Elecraft has done with their K3/K3S? 
Photo of Tim - W4TME

Tim - W4TME, Customer Experience Manager

  • 9197 Posts
  • 3557 Reply Likes
There is modularity built into the 6400/6600 primarily for serviceability and it may be used in the future to deliver optional feature and performance enhancements.  

I cannot comment regarding a comparison of one radio's build architecture vs. another.  I just don't have enough requisite knowledge of the K3's details to provide an informed answer.
Photo of Mark - WS7M

Mark - WS7M

  • 1357 Posts
  • 506 Reply Likes
I will upgrade to the 6600 but probably will be waiting for the fury to die down.  Let FRS get caught up some. 

I like the feature set in the 6600 personally.