How-To 2m and 70cm DEMI Transverters on a 6700 & Questions

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I have researched the forum for Transverter installation options/ideas and there are several threads floating around with information. It is a bit scattered so I thought that I would put my findings and decisions on a new thread that might be helpful to others.

The goal for me is to add the 2m and 70cm capability that I get out of my TS2000 to the Flex 6700. I want to have an all mode HF, VHF, UHF rig capable of working repeaters, SSB DX and SAT (even EME).  

After talking to FRS (Thanks Dudley) and DEMI (Thanks Sandra for your help) I have a better idea on how to proceed. But I would like suggestions or comments if you guys find holes in my current configuration idea.

The 2m part will be covered with the Amp-Preamp DEM 2MLDPA. In my case I went for the 60w version.

http://www.downeastmicrowave.com/product-p/2mldpa-60.htm



I added the following options:
  • LDREM-OPT for remote ON/OFF
  • LD-HP Common RF for a single connection to antenna
  • XVRT IN and XVRT OUT ports (Default)
For the 70cm part I selected the L432-28HP which is the fully assembled 28Mhz IF 60w output 440 Transverter.

http://www.downeastmicrowave.com/product-p/l432-28hp.htm





The image above doesn't have the TX IF and 10 Mhz ref input BNCs.

I wanted to be able to use it with the 6700 and the Flex 1500.
I added the following options:
  • Split IF configuration (this is important for Full Duplex)
  • IF Drive 0 - 100mW
  • HP Common RF Configuration (Single antenna)
  • DUAL LO OPTION: Allows the use of either the internal clock or external 10Mhz source.
  • Optional filters to be able to work at both ends of the band for SAT work and Repeater work.
  • I also went with the larger heatsink. 
I also added a 10Mhz reference HUB. The DEMI 10-4:

http://www.downeastmicrowave.com/product-p/10-4.htm



This is a very interesting device if you happen to have the GPSDO option in your 6700/6500. It allows you to use the 10Mhz reference from the Flex radio and input that into 4 devices. In my case I will use it to send a 10MHz ref to the 70cm transverter, the Flex 1500 and the Kenwood TS2000 with this TXCO replacement (http://www.vk3hz.net/XRef/XRef_Home.html).

Remember to add BNC 50 Ohm 1w  to the unused ports.



Now on to the schematic for the connection with the Flex 6700.



Which finally brings me to my questions and concerns:

  1. I have to share the XVTR port for both 2m and 70cm so, how do I tell from the 6700 to engage TX2 or TX3 based on the panadapter that is TX in SmartSDR? Those are the blue lines on the schematic.
  2. I see how if I TX in 2m I can RX in 70cm because I will TX out of XVTR and RX on RXB on the Flex (green line). But what about TXing in 70cm and receiving in 2m? Do I need another port in the DEMI 2m Amp to send the receive preamped signal into RXA? And if I do that? Where do I put a Magnetic Loop for RX?
  3. Am I missing anything in my configuration? Is this doable? 
  4. I have tested with dummy loads and I can move both the TX and RX frequency in 2m and 70cm while I transmit which should allow me to move to compensate for doppler effect when working SATs, but I can't move both panadapters at the same time... I can't find a way to sync them to move them simultaneously. I guess orbitron/sat32/hrd sat will have to take care of that. 
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EA4GLI - 8P9EH - Salvador

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Posted 4 years ago

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len

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Good luck trying to get the amp. I have had one on order since April 22, 2015.
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EA4GLI - 8P9EH - Salvador

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So I am not getting the one I order 2 days ago before Xmas???
 
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len

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They keep pushing the date out. My current ship date is November. We only have 5 days left, so I hold out hope.
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Mike - WB8CXO

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I finally received an email reply from DEMI a few days ago informing me they expect to ship my amp in Feb. THINKING ELECRAFT. Can easily sell them when the DEMI amp arrives.
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Roy Laufer

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I think of placing an order with DEMI as a "Zen exercise"...

Good luck with your order!
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Mike - WB8CXO

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LDPA was received in OCT 2016....  YAY!
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Roy Laufer

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Trying to re-invent the wheel<HIHI>?

I am confused by some of your choices, unless they are more about the other radios you would like to use these DEMI parts with?????

The LDPA's IN and OUT ports are not the same as the split ports of a transverter - the OUT port passes the IN signal out of the LDPA IF YOU POWER DOWN THE LDPA. With the LDPA powered, the OUT port has no signal.

I don't see the need to split your IF TX & RX (I can easily duplex with combined IF connections), and I don't think your choice of wiring the LDPA's XVTR OUT to your L432's IF TX is such a good idea (it will only bypass the signal when you turn the LDPA OFF). The 10 MHz hub only becomes important if you simultaneously connect your other equipment - in your simplified diagram it is superfluous.

The 6700's limitation is that TX1, TX2, TX3 must be manually enabled, until the software allows this to be automated with the selection of the appropriate band's transmission controls.

I am very pleased with the use of my transfer switch to swap transmission bands "on the fly" and for $50 it seemed like a bargain.

Perhaps I am missing something in your design?

Good luck!
Roy AC2GS
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EA4GLI - 8P9EH - Salvador

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Hey Roy,

Does this make sense?



The green dotted line it's supposed to represent voltage going to the RF Switch to energize it but I am not sure that will be coming from the Flex.
(Edited)
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Roy Laufer

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With the exception of the green line, this is the exact implementation that I am using successfully!

The green line won't work - it is the 6700's PTT input, not an output. Different transfer switch relays  are rated for different voltages. I have found 12VDC the easiest to deal with in my shack, and I believe it is the lowest voltage usually sold. The 6700's PTT only supplies a 3.3VDC voltage and the transfer switch's relay will be interpreted by your 6700 as you perpetually keying down to transmit. If it is simply a matter of supplying the power to energize the relay, I would suggest pulling some of your 12VDC (or 13.8VDC) from your shack's power supply with an inexpensive inline rocker switch (a latching foot switch could be used for handless switching if you would prefer this). Since you will probably need to flip your inputs from RCVR B to XVTR and vice versa, I think that the rocker is the simplest and least complicated method of dealing with the energize/de-energize control. 

You could use the spare TX1 as a simple output relay and apply an external voltage to actuate the transfer switch's relay (TX1 is rated for a maximum of 40 VDC at 140mA), but I would discourage this excessive degree of switching. To me, it's a just as much a  time consuming effort to enable/disable TX1 control versus actuating a small inline power switch to energize the relay when I want to transmit on the 70cm band. I do not foresee a time when I will need to alternately transmit on 70cm then 2 meters with each push to talk.

You could leave the inputs (RCVR B & XVTR) unchanged and have both panadapters set to transmit on XVTR and switch "on the fly" with the TX1 pin, but you would not be able to fully  Duplex in both 2M out/70cm in & 70cm out/2M in with that configuration.

All these configurations are like complicated logic puzzles. I triple checked my theoretical configuration before buying the parts, but still wasn't absolutely sure of it until I put it together and tried it out.

If I have confused you at any point, with my meanderings, feel free to ask whatever you would like.
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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I understand. I normally need to draw something to totally understand it. I need to get some bnc to sma patch cables. Thanks for the help. I am sure it will be useful to others as well.
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pa0bie

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DDUtil can do band selection with a USB-8 relay card or with a LPT->16 relay interface. The band selection will follow the TX enable on one of the two slices at 2m or 70 cm.
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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I found a $10 usb 8 relay board on eBay. thanks for the idea.
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David Warnberg

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Salvador... I want to follow this thread closely as I am proceeding down this path as well accept I elected to build my own transverters with the elecraft kits.. 432 mHz kit sitting on bench now, I will also add the thumbDV for local DSTAR repeaters when I get there..

Just an FYI on number 4, from my testing and playing with my ICOM 9100 (sold) your best best will be SAT32 or Orbitron, HRD does NOT handle frequency control for linear inverting SATS correctly as they say it will..

Thanks

David
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EA4GLI - 8P9EH - Salvador

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I think the Maestro might make it easier to do, if you can move 2m with one knob and 70cm with the other. Thanks for the Orbitron/Sat32 advice.

We can only dream that we could add a feature in SmartSDR to SYNC two Slices, right?
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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Any progress on this guys? Any of you received the Demi gear?
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Mike - WB8CXO

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Latest promise from DEMI was this February so I have two weeks to go. Fingers crossed.
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Mike - WB8CXO

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LDPA received OCT 2016...  :)
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Roy Laufer

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Well, my 2 Meter DEMI LDPA and "modified" 70cm DEMI transverter, as well as my transfer switch are "alive" and well - no problems here. I am happy with my purchases. I just wish it had a few less "bumps in the road" and delays.

I'm looking forward to reading if anyone else has followed my transverter path and how it worked out for them.
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len

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I must be on the S*** list. Still waiting for the Amp. Ordered April 2015....No news.
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K6OZY, Elmer

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This configuration seems to read like we can RX 70CM while 2M TX, but not RX 2M while 70CM TX. Do you think there is anyway to have it both ways?
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Roy Laufer

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With the transfer switch in place you can select to do UHF Tx/ VHF Rx or VHF Tx/UHF Rx!

I have it at my QTH and works very nicely!
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EA4GLI - 8P9EH - Salvador

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Still waiting for DEMI to deliver. It seems that we have an extra delay and we will get a newer version of the 2MLDPA

Temporary Delay notice http://01895fa.netsolhost.com/2MLDPA.htm

In the meantime I was thinking on my own setup.

Will it make sense to use a duplexer instead of a Relay Switch?

I am thinking that I can use VHF /  UHF Duplexer connected to the XVRT port of the 6700



For VHF the 6700 will TX out of the XVTR port, go into the Duplexer and send the VHF signal to the 2M amp from DEMI. The return goes back into the Duplexer and back into the XVRT port of the Flex.

For UHF the 6700 will TX out of the XVRT port and into the duplexer HF part, sending the signal into the 28Mhz IF IN of the UHF transverter from DEMI.

The return from the DEMI UHF transverter will go from the 28Mhz IF OUT of the DEMI transverter directly into RX A in the 6700.

This would allow to automatically send the right TX to the right device from the XVRT port of the Flex and allow for Full Duplex without having to manually switch any relays.

Any holes in my reasoning? Thoughts?
(Edited)
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EA4GLI - 8P9EH - Salvador

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I edited because I made a mess of the first post, put the wrong duplexer image. 
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Roy Laufer

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I see a significant problem with this. The XVTR will NOT be supplying its 100 mW output at VHF and UHF frequencies - the VHF will be 144-148MHz BUT the 'UHF' will be output at an IF in the 10 Meter range - it will only get upconverted by the transverter itself.

You also need to toggle the two PTT/Drive lines to select which DEMI box is triggered.

If one of your boxes has a separate IN/OUT IF port, you might be able to split the output with an HF/VHF splitter theoretically - it would be interesting if the diplexer loss and other factors would complicate matters...

My transfer switch cost me $39 - that's about the price for a diplexer...

Good luck!

(I read how DEMI ran out of supplies and is redesigning the LDPA as a pure pre-amp/amplifier rather than a part of an older transverter design. The box will be smaller (and colored?) but the maximum power will drop to 50 Watts.)
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EA4GLI - 8P9EH - Salvador

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I messed up the original post, I edited now putting the right duplexer that separates HF and VHF.

I already purchased the switch Roy, as per your advice.... I was just thinking that with the duplexer it offers fully automated operation, bar the separate PTT lines based on transverter map (which hopefully FRS will implement at one point).
(Edited)
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Mike - W8MM

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This could be a very nice way to do it.  

It all depends on how much isolation one needs to keep 144 MHz noise and birdies being generated from the 28 MHz IF of the transverter at bay.  Also, I'm unaware of the wide-band spectral purity of the 6700 XVTR output as far as noise messing up any full duplex operation you contemplate.  

If the duplexer doesn't have enough isolation dBs by itself, you could always add 144 and 28 MHz band pass filters after the duplexer to get more isolation.
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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The duplexer offers 50 dB isolation, that seems sufficient ....
(Edited)
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EA4GLI - 8P9EH - Salvador

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So here is a graphic with the duplexer as distributor of the signals

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K6OZY, Elmer

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Agreed, this makes it really difficult to use the 2M AMP + 70CM XVTR combo for full-duplex Sat work.   This is why I stated above that the answer may be to use a 2M XVTR instead of a 2M AMP.  I'm trying to find out if the 6700 will obey a XVTR definition for 2M overriding its native 2M RX abilities to see if a double XVTR combo would work on it.
(Edited)
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EA4GLI - 8P9EH - Salvador

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If you go that route the Diplexer will not do much for you so you have to add a switch to send to one or the other transverter... if you are adding a switch, might as well use it for the antenna return and keep the amp.
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K6OZY, Elmer

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Another option is that since most of the AmSat birds RX on 70cm, is to simply attach my 2M antenna to RX IN A/B and never transmit at all from it with a 70CM XVTR.
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EA4GLI - 8P9EH - Salvador

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Another option could be to enabled through a SOFTWARE patch to use ANT1 or ANT2 to TX on 2m.
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K6OZY, Elmer

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I think there is a HW block there because it has to go through the radio's PA and filters.
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EA4GLI - 8P9EH - Salvador

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This is only feasible in the 6700 that already has 144Mhz out of the XVTR port of the radio.
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David G4NRT / Z21NRT

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A very interesting discussion and one that gives me food for thought.

I am using three transverters on my 6500. A Spectrum Communications one for 4m and Kuhne ones for 2m and 70cm (actually I am using an HA1YA 2m one until I collect the new model Kuhne one at Friedrichshafen next week).

I have ordered / changed / reworked all three transverters to be dual cable IF.

My plan is to buy one Kuhne's Transverter switches so that I have one set of cables to the switch and then a set to each transverter which I can switch at leisure.  The switch also incorporates a PTT in and out.

Finally, I will be using a variety of diplexers to split the antennas due to only having one SCU in the 6500.

However, the diagrams above give me some other ideas which may work out cheaper or simpler!

This is a great community!

David G4NRT
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Simon Lewis

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for those switching multiple transverters round on a Flex this might interest you :)

http://www.w6pql.com/automatic_transverter_interface.htm
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EA4GLI - 8P9EH - Salvador

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Looks great! I might have to order one of these!
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Simon Lewis

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And if you're using Kuhne boxes .....

http://shop.kuhne-electronic.de/kuhne/en/shop/amateur-radio/converter-transverte/transverter/TR6SW++...

this is interesting as it can be driven from DDUTIL and a USB relay card to select transverter bands remotely
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David G4NRT / Z21NRT

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This is the solution that I am opting for as I have two Kuhne Transverters.

David
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Simon Lewis

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and another option for switching .....

https://www.tapr.org/kits_tass.html
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EA4GLI - 8P9EH - Salvador

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Things are slowly taking form in my eventual Full Duplex 2m/70cm Flex 6700.
I received the UHF Transverter, 10MHz HUB and Diplexer from DEMI.





This thing is big!!!



Below, 28 MHz span of UHF



This is what working SO50 should look like.

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David G4NRT / Z21NRT

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Bearing in mind that I only have a 6500 not a 6700, is there a way that I can do full duplex so that I can work satellites?  

Right now I have an Icom IC-910H for that but I'd much rather use the Flex with my two Kuhne Transverters.

The AMSAT paper that I have seen appears to use a whole bunch of switches but I am a little uncertain about which ones and what they do ....

Suggestions on the configuration and what kit I would need would be most welcomed ...

David G4NRT
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George Molnar, KF2T, Elmer

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Yes, full duplex works fine with the 6500. Use the XVTR port for uplink, and RXA for downlink, with appropriate converters or transverters. I use the Elecraft XV144 and XV432 simultaneously, to separate antennas.
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David G4NRT / Z21NRT

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Thanks George.  I shall give that a try ... I will also fiddle about with SATPC32 and see how that goes ... this is what I love so much about this hobby!  There is always something new to try and I still get a thrill making a QSO even after almost fifty years!

David G4NRT 
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Roy Laufer

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I have been following this thread, and following the logic of what goes where could drive the Mad Hatter even Madder!

I have lost track regarding what exactly is the desired result.

To put it simply I have an old DEMI 2M LPNA and a 70cm DEMI Tranverter with a single input/output and a microwave transfer switch.

Presently I can listen to any station on UHF and transmit on the VHF band OR receive on the VHF band and transmit on the UHF band, using my 6700.

Is that the ultimate objective??????

Roy AC2GS
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K6OZY, Elmer

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So Roy, Steve, your 70CM XVTR does not have Split IF?  Salvador's did.
(Edited)
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Roy Laufer

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Mine does not.
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Steve - K5FR

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Mine does not either.
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K6OZY, Elmer

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OK this why I've waited for so long.   Your switch method makes a ton of sense.  This is the switch in the picture.  It is what you are using for sure:  http://www.ebay.com/itm/Ducommun-DB-Products-TA1A31DK-RF-Microwave-Transfer-Switch-18GHz-12VDC-SMA-N...

Thank you for spending the time working these details out.  The XVTR is a very expensive purchase, and I don't want to buy it with the wrong setup.
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Roy Laufer

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I understand your trepidations. I drew out the logic diagrams, making sure I was building exactly what I needed. The proof of concept is that it actually works for me!

Sometimes you have to re-invent the wheel, and sometimes you get the benefit of someone else sweating the details and sharing with the class.

One of the great parts of this hobby is that we all help each other.

You don't get much of that with stamp collecting !
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EA4GLI - 8P9EH - Salvador

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Well... DEMI informs me that there is no way they can implement a mechanism manual or automatic to switch the signal path between transmit and receive on the 2M amp. They said they "require an addition of 3 relays or PIN diode switches within the 2MLDPA" for the amp to do what we need. I have no clue why... but I they say so....

This puts a dent in my plan and makes me reconsider the DEMI purchase.

Integration with Flex 6700 was a big PRO of the DEMI. Without that I do not see why wouldn't I purchases a Kuhne or any other brand if I have to manually switch the return path of my antennas.

It is very frustrating and expensive to try to make this radio work in VHF or 4m for that matter.
Not a very happy camper at the moment....

The main reasons to have 2 SCUs was, in one hand, diversity, (which is very rudimentary in SmartSDR right now) and on the other hand being able to work Full Duplex which is useful for Sat work. But then the whole VHF and transverter part of the 6700 is just not ready. You should have 2 XVTR ports out of the back of the radio because you have 2 SCUs... but that is not the case which limits things. I imagine people use the Loop ports for something, two of them... there has to be a reason to have those there....but I think 2 x XVTR would have made more sense. Two 6300 will actually give you more play... but you can't have both running on the same PC, because you can't have 2 instances of SmartSDR running on the same PC.

There are just a lot of holes right now....

I understand I can use external switches, and that I can automate with external relays... I can also use a Kenwood TS2000 for the SATs and a $150 SDRplay to RX.
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EA4GLI - 8P9EH - Salvador

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And even worst.... you could actually work Sats on Mode B with transverters for 144MHz having Split IF which makes having 144MHz out of the 6700 a disadvantage over the 6500. Oh well.
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K6OZY, Elmer

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I'm glad we were able to figure out this before you got that amp.   I have committed an order for a 70CM unit from DEMI built with a common IF and ordered that switch off eBay too.   Since I already have the 2M amp for other uses (FM Repeater and SSB stuff), I'm already invested.

I also confirmed that with the 6700, even if it has 2M natively, can still use a transverter for 2M on it to override the native 2M support.   This will let the 6700 behave just like the 6500 on that matter.
(Edited)
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EA4GLI - 8P9EH - Salvador

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But... isn't there a way we could make use of the 2 SCU and get 2 XVTR ports?
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David G4NRT / Z21NRT

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I have given up on trying to make all this work with transverters on my 6500.  I have sold my Kuhne transverters and used the money to buy an IC-9100 which plays perfectly well with SatPC32 and all the other applications I want to use.  

In the end discretion was the better part of valour (as we say on this side of the pond!).

David G4NRT
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Steve - N5AC, VP Engineering / CTO

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Official Response
With SmartSDR v1.10, we will be introducing the capability of adding cables to the FLEX-6000 that will provide CAT and/or BCD/binary outputs.  The system is quite flexible and we'll do a post on this soon, but I wanted to point out a couple of products that Downeast Microwave has that will allow simultaneous, full-duplex 144/432 operation on the FLEX-6700.  The first is the DEMI LDPA (low drive power amplifier) which can be found here: http://www.downeastmicrowave.com/product-p/2mldpa.htm  This amplifier will put out high power on 2m from the low output on the FLEX-6700.  If you order the LDREM-OPT with this, the unit will ship with a USB cable that plugs directly into the FLEX-6700 which will allow complete automatic and/or remote control of the LDPA from SmartSDR.  

The second one is a new switch/diplexer that allows operation of a 432/28 transverter in conjunction with the LDPA, model name DIPS: http://www.downeastmicrowave.com/product-p/dips.htm.  With both of these and a 432/28 transverter you can have a full-duplex 144/432 station for satellite or terrestrial operation.  The DIPS PDF above shows how to connect the system.  We expect to have a more complete description on how to do this including the software setup in the next few weeks.
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Roy Laufer

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"All's well that ends well."

I am glad that the powers to be have come up with an elegant solution to the problem.

In the end, I am fine with my setup, which only requires a single Rx and XVTR port and spares the other RCVR port - perhaps for that pre-distortion correction implementation, when using a linear amplifier, one of these fine days.

Have fun talking to things circling this crazy, crazy world <grin>!

Vy 73,
Roy AC2GS
(Edited)
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K6OZY, Elmer

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The problem with this is that we ordered our 70CM DEMI XVTER with combined IF.  This design requires split IF.   Uggggggh....
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EA4GLI - 8P9EH - Salvador

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I got lucky. Along the way I figured I was better off with separate IF on the 70cm transverter.
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pa0bie

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Just removing a relay in the 70CM DEMI XVTR with combined IF and ad a BNC would solve the problem.
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EA4GLI - 8P9EH - Salvador

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Good point. I was going to suggest to Chris to send it back to DEMI to make it separate IF and then have them return it together with the new purchase of the DIPS.
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Lee - N2LEE

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Wow, Roy AC2GS is right, this thread is insane and makes my head hurt. 

I love my Flex and would like to start working satellites with the 6500 but I can't help but feel like using the Flex is trying to cram a round peg in a square hole.

I hate to say it because I am a total Flex convert, but for working satellites I think a knob radio is much more practical and more cost effective.
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David Warnberg

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Lee.... I'm working SAT's without issue with the FLEX 6500, 2 Elecraft Transverters, and switches... for software I'm using SATPC32.. it controls both slices (one open for TX one for RX) and it also points my antenna's (controls the Yeasu G-450A)

To log my contacts I use Log4OM which tracks the frequency as well as the SAT worked (yes it has a SAT mode as well)

It's not as difficult as this thread makes it out to be.

FYI.. I sold my ICOM-9100, working SATS with the FLEX is easier because I can SEE the sat appear on the scope, see where a QSO is taking place and tune to that freq

David
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David Warnberg

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Here it is in action and as you can see XW-2D has some noise in the center of the frequency.

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Lee - N2LEE

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This looks like where I want to be as well. Interesting that you sold your 9100 because that was the other option.

Thanks for the explanation.
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David Warnberg

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Lee, feel free to reach out to me if you have questions, e-mail is good in QRZ..

I'm trying to put details of setup on my webpage but haven't gotten there yet, also have a bulliten board I just setup and trying to upload information there as well just so much to do and so little time to do it.



Call sign KK4QOE, web site kk4qoe.us
David
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Lee - N2LEE

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David, thank you very much for your offer and I might just take you up on this.
If I can repay the favor by helping you with any web site stuff let me know.

Lee
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EA4GLI - 8P9EH - Salvador

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It is very close to be ideal for sats. But right now it is the software that is falling a bit behind. We need to be able to either sync 2 slices to move them in unison or opposite of each other with a Flex control or a second option, allow for the use of 2 Flex controls. Having a visual clue in smartsdr to the status of the TX relays will also help. Remember to use your profiles.
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Lee - N2LEE

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DOH ! of course how could it not.

I might have read that the FM birds automatically compensate for the uplink frequency because it's only one channel, is that possibly why I got this wrong ?

It certainly makes sense that the doppler is an issue on a linear transponder.

Help me out here, do I have this correct ?
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George Molnar, KF2T, Elmer

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Nope, you need to move both. MacDoppler is what i use for satellite automation, and it handles everything with aplomb.
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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No worries. I am a newbie on the birds. The 6700 could be a fantastic tool for Satellites, right now, it is tough at times. Most of the "best practices" based on superhet radios without panadapter don't really work with SmartSDR. And SmartSDR has not been really designed to work with Satellites. My current, most comfortable approach makes use of the flex control and I mapped a click on the main wheel to switch between vfos.
Logging not always works due to the vfo a and vfo b paradigm and it is too bad that I can't really use slices C through H at all if I want to log the qso. Most Sats only give you a few minutes to get things shorted out.
On the other hand, seeing all the action is quite amazing.
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John Kludt

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Read the entire thread and I do have some question.  Using a 6700 with version 2 SmartSDR.  The rest of the station is a 2MLDPA and a Demi 70 cm transverter with the DIPS switch set up as per the DEmi diagram.  My question relates to the SATpc32 setup.  I guess you use the TS2000 option.  Given that there are 2 SCU's involved, does SATpc32 see one "radio' or two "radios"?  That has obvious implications for the setup of SATpc32.  I have tried both options and cannot get either to control the frequency of the A and B slices.

What have others done that has worked?

John
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Justin - KL2D

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I have the DEMI 70cm and DIPS on order, but I have simulated the 70cm transverter (the radio does not know it isn't physically attached) and used MacDoppler and DogparkSDR to control everything and it works great. The radio frequencies track perfectly. I am (hoping to) set up my az/el rotator today (G5500), so I will be able to report on MAcDoppler's ability to control it via AMSAT LVB, but if that goes well everything should track the sat automatically. I couldn't get MacDoppler to control the slices in SSDR, even though MacLogger controls them just fine. This could very much just be operator error too hi hi. 

I usually run SSDR in a windows 10 VM in Parallels, but DogparkSDR works really well with MacDoppler so for sats I will use that. I know that doesn't help if you aren't a Mac user... but thought I'd throw it in here.