transverter and FLEX 6600

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  • Updated 1 year ago
I'm need help- when ordering a Transverter  
they offer this Available
OptionsIF ConfigurationCommon IF
Split IF

RF ConfigurationCommon RF HP (+$35.00)

Split RF

IF Drive Level-20dBm to 0dBm

0dBm to +20dBm

1W to 10W

PTT PolarityLow (GND)

High (>1.7V)

Local Oscillator StabilityStandard

High Stability 0.28ppm (+$45.00)

Custom IF

Standard IF - 28MHz

Which option do I need my set up is FLEX 6600  2m amp and 432 amp  so puzzle which options i should do?

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James Kennedy-WU5E

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Posted 1 year ago

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Tom Worthington

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I use a DEMI transverter (2m) with separate Rx and Tx.  +20 dBm input is fine and easy to adjust with the Flex controls.  PTT low is standard (I think) and will switch the Flex properly.  I use the 10MHz output from my GPS locked Flex to keep the transverter on frequency with a standard 28 MHz IFoutput.  I use it for EME operation.  Once it is setup in the Flex it operates without any problem.
73, Tom, NH6Y
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Tom Worthington

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I should have said, the first choice is: do you want to run separate Rx and Tx coax cables to your antenna?  If you want to put a preamp at the antenna then you will need to add a T/R relay at the antenna and run two cables.  In that case you will need to ask for separate Input and Output connections on the transverter.  If you decide to use a single coax to the antenna and use the T/R relay in your amplifier then you want the combined output option for the transverter.  With your Flex you can use either a combined IF or separate Tx IF and Rx IF.  I run separate and select RX_A for the receive antenna and XVTA for the output antenna.  If the transverter has combined IF then you would select XVTA for both the receive or transmit antennas.  
73, Tom, NH6Y

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Watts - K4QJZ

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I should ask first what do you want to do with 2M and 70CM? The configurations can be optimized based on what you want to do such as Satellite work or Terrestrial such as repeaters and DX. I wanted to do both if I could, you can.

I recently purchased two units, one for 2 Meter and one for 70CM, in both cases the manufacture Q5 (the manufacture of the DEMI, Down East Microwave, Inc., units) and the folks at DownEast were very glad to discuss my applications and the pros and cons of the different configurations.

I hope to use the units for both areas of interest, Satellite and Terrestrial DX. Below is my configuration for each and a short note why, hope this helps. Note: I do not have a 10MHz reference but wish I did but it’s not required to start. (There is lots of past discussions on the accuracy of the VHF side of the 6700 with many saying the GPSDO option (Internal 10MHz reference option) is really needed? Only tried the repeaters in the area so far with no issues?)



1.     50 Watts (max power I would need for Satellite work and reasonable for local repeaters, etc.)

2.     Antenna out, Common TX/RC (RF Option) I am using the same antenna for transmit and receive on 70CM and at 50 Watts one can purchase quality RF preamps which will RF sense and switch themselves in and out as required if needed.

3.     Separate TX and RX (IF Option) needed to work duplex Satellite comms, very helpful to know how you sound over the satellite and the manufacture recommended the configuration for satellite work with 2M up and 70CM down or 70CM up and 2M down. (You will also need to purchase their DIPS device, duplexer/switch) (As noted in the previous Email you will drive the unit via the transverter port and receive via RX-A or RX_B)

4.     IF Drive, -20db to 0dbm (Matches up very well with the transverter output level on my 6700 (100 Watts on the SmartSDR software scale when using the transverter port will now equal 100% out.)

5.     Keying option, PTT-L (to ground) matches the TX ports 1-> 3 output levels, you will use one of these to tell the transverter when to transmit.

6.     One other option to allow dual use, order the wideband Optimized preamp (430-450MHz) internal.


1.     75 Watts

2.     RF Output Common

3.     RF drive level, 10MW max

4.     LNA Option (yes via a fused Coax bias) this support a future preamp ant the antenna which get its power via the coax cable.

5.     DC Power Enable, Remote (my station gets more use remotely and it makes it easy to switch between the two transverters as the Transverter signal from the Flex is automatically passed to the 70CM transverter if the 2M unit is off.) I can control this via the Flex software using the optional remote cable.

6.     LNA enable, Remote again as I can control this via the Flex software using the optional remote cable.

7.     Transmit Enable, Remote again, I can control this via the Flex software using the optional remote cable.

8.     Sequencer Enabled

9.     DIPS control options: be sure to order the Remote option (RCA connector)


Hope this helps, I am still learning as I go but as I said before the folks at both companies were very helpful and I did not feel they were trying to sell me on options. Others may have different suggestions, this is what has worked for me.