Satellite transverters with 6500 and SSDR v3.1.8 - Ordering/Configuration Advice

Todd Rodgers

Hello All,

I'm getting ready to start to play with satellites & my 6500. I've searched for the "definitive" guide, but have lingering questions. Ideally, I'd like to operate full duplex with two DEMI (Q5) transverters (2M & 440). Somewhat wishing I went for a 6700 as that would have solved the 2M part.

The January 2016 AMSAT article by W5RKN seems to layout much of what I need to do. Is it as simple as just properly switching the XVTR (for transmit) and Receive A (for receive) ports between the two DEMI transverters? I think I have a good handle on how to get SSDR properly configured, and must still investigate what additional software needed to deal with Doppler shift and such (I do run HRD, and will try to get it's Satellite functionality into play (or other controlling software).

What configuration of the DEMI transverters is recommended (although I understand one can change the configs with little effort).

Just wondering if anyone out there has a quick write up or description of how they did it with a 6500 (and, ideally, the DEMI transverters)?

Any pointers, most appreciated.

Todd, KC1SQ

John WA7UAR

This is one of my favorite community articles about satellite configurations and it includes helpful links to 3rd party postings from Flex users as well — I include it here for your reference. Hope it is helpful for you Todd.

https://community.flexradio.com/flexr...

Rick N0VT

Todd--before you invest in the transverters, do a test of your rig using full duplex.  For instance, do the exercise on adjusting your audio where you transmit on an XVTR port and listen on a second slice.  The audio delay you hear coming back will also be present when you try to work sats full duplex.  If you want to listen to your downlink you'll have to put up with that.  I just found out a week or so ago--after bringing it up as a "problem"--that's this is an inherent characteristic of using FDX.

KF4HR

Tod - I own a Flex-6700 and began heading down the road to satellite operation with my Flex.  I purchased the DownEast Microwave 2MLDPA which seemed to work well.  Unfortunately I had nothing to compare it to at the time.  Then (perhaps a bit too late) I began to add up the expenses involved (UHF Transverter, UHF Amp, 2MLDPA, and other necessary components), and the complexity involved.  I came to conclusion I'd be better off putting the money in an ICOM IC-9700. 

After my IC-9700 arrived, for grins I ran a receiver test using several local FM repeaters (using the same antenna), comparing my Flex-6700/2MLDPA setup (the 2MLDPA's receive preamp was turned on), with my IC-9700.  I found the IC-9700 to have a much more sensitive receiver.  I need to run more tests to determine whether the lack of 2M receive sensitivity has to do with my Flex, or having the 2MLDPA inline, but bottom line, I gave up on my idea of using my Flex as a Sat or 2M EME Rig. 

Todd Rodgers

John, Rick, Ralph -

Thanks for the valuable input/replies. I must admit, I've considered the IC-9700 for this new interest in satellite work (doing the same $$$ math). Plenty of station automation in play, so... running more than one rig... not a really a problem. Just seemed like with the right gear/configuration I could experience the same HF experience I love with the 6500 on VHF/UHF. More homework required, perhaps.

And, I'd welcome any other insights from users here. Success, happy vector, etc. with going the Flex route for full duplex satellite work.

Thanks!

Alan

Todd, I operate "remote" from my radios, including the satellite equipment, so the Flex and PC control of all aspects has been the center of how I work satellites.  Here is a screenshot of my Satellite Station.  Everything is on one PC screen and remote from the radios:



My experience using a Flex 6600 and Q5 transverters has been very favorable.   Setting up the Flex and the transverters was straight forward and one of the more simple tasks in the overall scheme.   I found setting up the tracking software, the antenna interfaces, and  the antenna building to be much more of the challenge.  The later challenges will be common to whatever radio you select.  For me, learning and implementing new technology is the fun of radio, so this was fun....lots of moving parts!

I specified Q5 transverters with a 28MHZ IF, and common IF/RF inputs/outputs (TX/RX switching is done internally to the transverter).

I am not sure but believe that the Flex 6500 has two XVTA BNC ports.  If so, you are ready to go, one for 2M and one for 70CM.  Setting up the transverters portion of the satellite station with a Flex 6600 is nearly "plug and play".  The tracking software, the logging software and the antennas are nothing near "plug and play".

The Flex 6700 is not "plug and play" because many use its internal 2M receiver and that requires split IF and split RF on the 2M RF  with external relays for TX/RX and antenna selections.  You also need a separate 70 CM transverter, with the same switching additions.  It can be done, but just saying, it is more complex than the Flex 6600 setup.


I use SATPC-32 Satellite Tracking Software.  Other brands either do not do the doppler conversion well or do not interface with the Flex 6600.  There was a steep learning curve, but I got through it.  I found the AMSAT community to be helpful.   The developer of SATPC often responds to questions withing he hour.

A nice feature of the Flex is the ability to do full-duplex.  Doing so, you can hear your transmission from the satellite.  There is a small delay, but not enough to be a distraction.  The Flex panadapter makes seeing and finding all the stations on the satellite passband (for the linear transponder satellites) very easy.

A nice piece of software to have is FlexSatPC.  FlexSatPC provides automatic switching of the Flex profiles for each Satellite.  It also builds the profiles if you wish, based on downloaded Keppler Data.

Antenna Pre-Amps are site-specific.  I do use them based on the 150 ft of coax between the antennas and my radios and for 70CM, that is 7 DB of loss.  The Q5 Transverters include adjustable RF gain on RX, so I would be careful using sensitivity comparisons to other rigs.  A more important parameter for Satellite reception is the noise to signal ratio.  I do not know about other vendors, but the Flex has excelled for me in this area.   I have read on the AMSAT community of others frustration with S/N, especially those in urban areas.

Alan
WA9WUD

Norm - W7CK

I too went with the 9700.  It works very well and is a simple solution that is all in a single box.  Transverters, amps, and all the cables for 2m, 70cm and 23cm is crazy complicated and just makes it far too easy to have problems with rfi and other failures do to all of the extra hardware, cables, power supplies etc.

K5WH

6600M sensitivity question with Q5 transverters.

I have a 6600M that I am trying to get my Q5 VHF and UHF transverters working with. The interconnecting was quite simple, as I have been using these on my HPSDR Hermes Lite2 systems for more than a year, so the configuration was very much the same, after setting up SatPC32 to control everything.
These are working fine with the local VHF and UHF repeaters, although they are far stronger than any of the satellites of course.
But, I seem to be having a real problem with signal strength from the birds in this configuration.
I have full confidence in the Q5 transverters, as I have been using them just fine in my other environment, so I'm certain I must not have something configured properly on the Flex side.
What are people using for the RX gain setting? When I have it at the default of 0, there is no noise floor at all. If I set it at -5db or even up to -50db, it raises it very nicely, but I still struggle to hear the satellites properly.

Any suggestions on that would be greatly appreciated, as I would really like to nail this one down.
many thanks, Walter/K5WH

Alan

Walt

My Flex 6600 / Q5 does a great job on receive.

I have the RF gain for 2M and 70cm, on the Flex, set to zero.

I did follow the Q5 instructions for setting the RF gain on the transverters.

I would first suspect your antenna/pre-amp/feed-line loss as the cause for poor reception, especially on 70cm. In my case, I have antenna gains in the neighborhood of 10db and feed-line loss of 8db (70cm) and 3db (2M).

I have 6db of pre-amp gain at each antenna, which I can switch in / out. I normally use the pre-amp on 70cm but seldom on 2M.

Alan

WA9WUD

K5WH

Many thanks Alan for the reply.
Do you happen to have a link to the Q5 instructions that you mention here?
I used the normal Q5 documentation when setting them up initially, on my previous system, but is there something specific to Flex environments perhaps?
I have used these transverters for more than a year just perfectly on my previous system, so I'm certain the antenna system is ok, as it's only an issue with my current Flex environment, which is why I'm sure I have something not set right somewhere.
Thanks for the tips. When I turn the RF gain down on the Flex, I cannot receive the distant repeaters in the area, so it does appear to drop the sensitivity down quite a bit, of which I need the opposite of that.
thanks, Walter/K5WH

Alan

Page 5 of the manual. Here is a link.

http://q5signal.com/image/catalog/L144-28r1A.pdf

Below, are the instruction to adjust the transverter RF Gain:

Alan

=============

1. On the bottom of the transverter, verify the TXIF and RXIF gain controls in the transverter. Turn the RXIF control fully clockwise and the TXIF control counter-clockwise. This is maximum attenuation on Transmit and minimum attenuation on Receive.
2. Observe the noise level in the transceiver on the “S” meter and by ear. If it is too high, adjust the RXIF gain control in the transverter counter-clockwise until a slight noise increase is heard in the transceiver or just a slight movement in the “S” meter is detected. Power the transverter on and off to verify the change. The RXIF gain may be increased beyond this point, but it will start to degrade the dynamic range of your transceiver. It is all user preference. If you plan to use an external or mast mount LNA, this level will need to be re-adjusted. Find a signal on the band or use a signal generator to determine correct frequency, or minimum signal level.

K5WH

Thanks Alan,

I went through this on my previous radio, so maybe there's a difference in the Flex to require it again.
I'll give that a try.
thanks, Walter/K5WH

K5WH

An update on this.
I finally stumbled onto the root of the problem I was having with this setup.
Watching one of mike's great Flex videos on transverters, there was a very critical requirement mentioned, of having a COMMON IF for the transverter. I have previously been using a SPLIT IF on my HPSDR Hermes environment.
I made the simple modification to the Q5 Signal transverters and everything is working perfect now, and worked a dozen stations across multiple satellites today.
Life is good again, in the satellite world. :)
all the best,
Walter/K5WH