6400 Receive Antennas

k9bm .

Another new 6400 user dumb question:  When I bought this radio it claimed to have "2 independent receivers."  So I create 2 panadapters, and create a slice in each.  On the top one I put the band on 20 meters, and on the bottom one I put it on 6 meters.  I have my 20 meter connected to antenna 1, and my 6 meter connected to antenna 2.  But regardless of what I do, when I set the 6 meter slice to antenna 2 it also changes the 20 meter slice to antenna 2, and vice versa.  Is this a defect, or operator error, or did I buy the wrong radio?

Brad K9BM

Mike VE3CKO

The 6400 has one SCU, spectral capture unit, and the the 6400/6700 have two SCU's. You can open up multiple panadapters on the 6400 but they would all be using the same antenna since there is only one SCU.

k9bm .

So how does this, by anyone's common sense definition, constitute "2 independent receivers?"

Mike VE3CKO

Your 6400 is working as designed. To achieve what you are trying to do, which is one panadapter on 20m ANT1, and 6m ANT2, you cannot do that on a 6400. However you can with a 6400 or 6700.

k9bm .

OK, I guess I'm too **** to own a Flex.  It's FOR SALE, for anyone reading this, 3 months old in factory carton, automatic antenna tuner and hand microphone, $2,000 shipped in CONUS.  I'm ordering an Icom 7610, it's $1,000 cheaper than a Flex 6600 and actually DOES have 2 "independent receivers" as far as I can determine.  Please post if interested....

Alan C

I think Mike meant 6600 or 6700

Mike VE3CKO

opps, yes 6600/6700 typo, sorry Brad

k9bm .

Jim you are obviously correct.  My point is that Flex markets the 6400 as having "2 independent receivers."  What exactly is independent when you have to use the same antenna?  How many folks have a log periodic that covers from 20-6 meters?  I don't see anything "independent" about the alleged 2 receivers in this radios, it simply has split receive off the same antenna which mid-level dial radios have had for the last 40 years.  Shame on me for not asking more questions before buying....

Again, the radio is for sale, under the factory warranty, you get the antenna tuner and shipping for the price of the radio alone.  I'm moving on to a radio that does in fact have 2 independent receivers....

73, Brad K9BM

Mike VE3CKO

I remember when I was looking to upgrade from the 5000A  was contemplating 6300, 6500 and 6700. At the time I choose the 6500 and doing the research knew that it had only one SCU was disappointed I could not receive from two different antennas at the same time but I knew what I was getting into.  I was very happy with it, but eventually upgraded to the 6700. 
I suggest before you make a rash decision do your research, see what others are saying about the 7610. SmartSDR and the 6xxx series has so many advantages and you may come to the conclusion as many are, the 6600 is well worth the difference.

WQ2H - Jim Poulette

Brad,

Just to confirm - I don't have experience with the 6400, but the FDX mode and SO2R operation do function correctly on the 6600M. Technically the 6400 does have "two receivers", but does not have two "independent SCUs". As Mike suggests, I think that's the issue. 

Not exactly sure what you're trying to do, but you may want to double check if the Icom actually allows you to monitor a channel while transmitting on the other. It advertises "two receivers" just like the 6400 - but there is very little other information that I can find. If you really want SO2R capability an option could be to upgrade to the 6600 (4 independent receivers and 2 SCUs). The learning curve is a little longer, but I'm finding it well worth the extra effort.

For me it was an SDR toss-up between the Yaesu, Icom, or Flex. In the end I was just more comfortable with the Flex, even though the learning curve is a little longer.

In any event, good luck!

73 Jim, WQ2H

Ken - NM9P

Brad, One thing I did that allowed me to use HF dipoles and a 6 meter antenna at the same time on one antenna ports was to get a Comet CF-360 "duplexer" which splits one antenna into two ports - or combines two antennas into One port.  One for 1.8-30 MHz,  and the other for 49-470 MHz.  I was able to use the antenna on two ports.  

You might find that as a simple way to split your LP to allow using HF on ANT1 and 6 Meters on ANT2)  giving you what you want.

I haven't done it this way, because I was combining two antennas into one port, but it should work.

Ken - NM9P

k9bm .

Ken, that's a really good idea and I would jump on it if I wanted to sell my 160-6 meter solid state amp.  But after scratching my head half the afternoon I just can't up with a way to configure a 6 meter antenna and an HF Yagi to use with the Flex 6400.  All I want to do is monitor 6 while working HF, and I seriously feel someone at Flex should review the dictionary definition of "independent" and then revise their marketing of the 6400. 

An "independent" receiver does not require the use of the same antenna as another receiver, it means 2 separate radios in the same box.  We can talk esoterica all afternoon about spectral capture units and slices, but unless you're a well experienced SDR user or experimenter you will interpret the marketing claim of "2 independent receivers" exactly the same way I did....

Clay N9IO

Brad, The 6400 is most similar to the 6300, 1 scu, 2 slices (receivers.) I started with the 6300 and honestly use my 6600 the same as I did the 6300. Similar to the Antenna Genius I use a SixPak . I set it up to receive on antenna 1 side of the switch and Transmit on the B side.but I am on the same band beit DXing or ragchwing. Two separate bands with two separate antennas is achieved with the 6600 and 6700 models. No disrespect but sounds like you're about to make another under researched decision.

Craig_KØCF

Be aware that the Icom IC-7610 can NOT use two antennas for the two receivers. It has only 1 ADC and works in the same way that the 6300 and 6400 do. Download the manual and take a look at it. If you want full duplex receive, you will have to get a 6600 or a 6700, both of which have two SCUs.
Or the Icom IC-7851, which is a LOT more money than even a 6700!

k9bm .

Thanks Craig, I did check and it appears you are correct.  This is all WAY too much for what I'm looking to do.  I think I'm better off just forgetting about 6 meters until I get a ping from a spotting reflector, or just use my old Icom 756PRO hooked up to NiMM which is perfectly capable of handling SO2R.  In fact, I could buy 2 or 3 dial radios that can be computer interfaced before I would reach the cost of an SDR radio with 2 SCUs and true "independent receivers."  I appreciate your help....

Doug Hall

Craig,
The IC-7610 Advanced Manual page 78 shows two ADCs with the ability to select a different antenna for each receiver. Is this incorrect?
73,
Doug K4DSP

Craig_KØCF

Doug, I stand corrected. The review that I saw was wrong. However, the manuals are very brief and vague about dual receive operation. Others have suggested that it does not do full duplex. I would suspect that both receivers are muted when transmitting, which would mean that it would not work in an SO2R contesting situation. But as far as I could find, Icom doesn't say one way or the other.

p.s. I owned an IC-7600 for five years and loved it. But my 6500 is better.

Greg N8GD

I've never done so, but why can't you use the receive only input (RXA IN) or the transverter input (XVTR-A) for your 6M monitoring?  You'd have to switch to the active transmit slice and change to the 6M band to transmit, though.  The RXA IN port is receive only and goes directly into the same spectral capture unit (SCA) that your ANT 1 (slice A?) is connected to, but with no transmit capability.  It will permit that receive only capability on a separate antenna, however.

mikeatthebeach .

You can use a 20meter thru 6meter Hex Beam on that Flex6400
73 Mike

Rick WN2C

I haven't seen where Flex claimed to have 2 independent receivers on the 6400. From the Flex website is the following for the 6400...

With a PC, laptop, or Mac client you can utilize up to two 7 MHz spectrum/waterfall displays and independent receivers to revolutionize your view of the bands. Its two receivers can be placed simultaneously on any band and mode with instant QSY between VFOs. Digital mode operation is a dream with no sound cards, cables or boxes needed.

What it is actually saying is that you can have 2 slices open on any band.

K4MT

Your correct. Comment above is as clear a peanut butter.

I like you would assume independent receivers not slices.

Say what you mean or mean what you say. Customers can only believe what they read when no familiar with a product.

Bill -VA3WTB

It is more about understanding what SDR is and how it works. In SDR the number of SCUs and or ADCs tells you all you need to know about what a radio can do.

K4MT

whats wrong with advertising that is aimed to new users that might not understand. Not all users are engineers. As usual you take the simplistic fan boy answers.

The objective of advertising is to educate the uneducated and not give confusing information that spawns  a discussion  like this

Mike VE3CKO

We are all responsible for our own station. Seasoned ham or new to the hobby, when we make mistakes are do not do proper research, if there is any blame we must just look in the mirror.

We bite the bullet and we learn from our mistakes.

Ted VE3TRQ

I hate to break it to you, but the objective of advertising is to sell product :-(

WQ2H - Jim Poulette

I find this thread intriguing, and I didn't find the remark condescending in the slightest. Although, frankly, the innuendo of misrepresentation clearly could be.

Unfortunately, as a career engineer, I deal with similar scenarios almost every day.

The definition of 'receiver" is fairly clear. Maybe even widely accepted and defined. Throw in the word "independent" - OK, that's clearly a little marketing. What is not clear is any further performance interpolation from a potential customer. If I can speak freely, that sounds more like wishful thinking or, poor planning.

73 Jim, WQ2H

k9bm .

Let me ask you this:  If I sold you a pair of Drake 2C receivers with physically welded together cases and the antenna input ports physically welded together with hardline to a single input and I called them "2 independent receivers," would you consider that a fair marketing representation?  Now what if I sold you the same two receivers truly separated, packed in separate boxes.  Would you now believe you had received "2 independent receivers?"

As pointed out, both "receiver" and "independent" are well understood common language words, and I feel it's at the very least disingenuous of Flex to stand on some arcane usage technicality of SDR engineering design.  Was I misled?  You bet I was.  Should I have done more homework?  Obviously....

Brad K9BM

Ted VE3TRQ

I would never purchase a transceiver without first looking at a signal flow diagram for the radio. A very perfunctory review of the 6400/6600 signal flow in the 6400/6600 Hardware Manual shows immediately what the capabilities of the radios are. If someone with an amateur radio license cannot read such a diagram, they have no business operating a transceiver. Maybe that's a bit strong, but we really DO need to be a bit more than appliance operators.

k9bm .

Yeah Ted, that is a bit strong.  I was first licensed in 1967, I built my first homebrew electronic keyer that summer on the chassis of a scrapped 5-tube table radio.  I made my living for a few decades as an RF Engineer designing cellular networks and microwave links.  I thought I had researched SDR radios pretty well, I talked to a lot of hams, including some on this forum, and yes I relied upon some of Flex's marketing when they use common, nontechnical terms like "independent" and "receiver."  Shame on me?

You can say I was uninformed, but do not call me an appliance operator.  I was homebrewing ham gear decades before your parents met....

Ted VE3TRQ

That comment was not directed at you specifically, Brad. Just a general comment that we are all responsible for our own equipment decisions, and there is lots of data out there to help make up our minds - just need to look for it. (By the way, I put my first transistor into a circuit in 1959 :-)

k3Tim

CK722 - Germanium - the good old days....