How to use the Transverter

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  • Updated 6 months ago
So, I've never used a transverter before and I have some foundational questions.  I have almost all the DEMI and Q5 Signal stuff here now.  But, a few questions remain.

So, if the IF for the 1296 and 430 xverters are both 28 MHZ, and the, for example, 1296 xverter goes from 1296 to 1300, or, 34 mhz, and the 70 cm gores from 430 to 450 Mhz, how does one actually "see" all that spectrum?  In other words, if the IF is 28 mhz, and the xverter has a bandwidth that is measured in the tens of MHZ how do you tune  that??????

I'll have more questions but I wanted to start with this one, can't be the only guy who doesn't know!!

Peter
W2PP
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W2PP

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Posted 6 months ago

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Rick - W5FCX

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Based on some YouTube demo videos I found, if the bandwidth of the transverter is less than the ham band of interest, then you can create several mappings to access each band segment.  For example, if the transverter bandwidth is 2 Mhz, then on 2 meters you can create 2M-1 and 2M-2 segments that map 28 Mhz to 144 Mhz and 146 Mhz to access the entire 4 Mhz.  That's my understanding of how to do it.
(Edited)
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W2PP

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Thanks Rick, but I may not have been clear.  I just went in and created two xverter bands
1296 and 430 mhz.  It looks like the radio takes care of all that math. 

 Meaning, the IF might be 28 mhz, but it looks like the radio actually, in the case of 430 to 450 must transmit at very low power from 28 mhz to 48 mhz to make the conversion work. 

 In the case of 1296 to 1300 mhz, the radio must transmit at low power from 28 mhz to 32 mhz,   Is that correct?
Peter
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Rick - W5FCX

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The transverter output is sub-QRP levels up to a maximum of 10 dBm as I recall.  I have one of the Ukranian 2 meter transverters, without the attenuators, on its way, which can produce up to 10 watts or so with just a few dBm in.  I also purchased an RF Concepts 2-17 2 meter amp that will boost the transverter output signal level to 170 watts or so (with only 2 to 3 watts in, to keep the IMD low).

So yes, some form of amplifier is likely to be required to transmit at higher power levels.
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W2PP

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Rick:
    The transverter puts out plenty of power.  I'm speaking about the IF from the radio, take a look again at my question and you'll see that's what i'm trying to wrap my head around.  Perhaps someone from Flex will chime in and let me know

Peter
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Ken - NM9P, Elmer

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A 2meter transverter with 28 MHz IF generally translates 144-146 down to 28-30 MHz. But with the Flex, the Transverter port will output beyond 30 MHz, so for example, 144-148 MHz will translate to 28-32 MHz with no need to program additional transverter profiles, as long as the transverter will handle it.

Your 1296-1300 is only 4 MHz, and would likely be covered.

Even though the 70 cm band goes fro 420-450 in the US, most transverters are not tuned to cover ALL the band.
Most are tuned to cover either the weak signal section or the satellite section in the low end of 430 MHz. Some of them are broad enough to also cover the FM segment of 440-450, but not all of them will.
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Ken - NM9P, Elmer

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Another advantage with the Flex is that once you set up the transverter and calibrate it, the frequency display and Panadapter will show your actual frequency.
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W2PP

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Thanks that’s what I thought. Well the DEMI 70 cm I have was setup for 430 to 450.

I think this is where my Flex 6700 is again going to shine. As you noted it shows the correct frequency. Most importantly for satellite work the panafall will really really be useful.

Cost wise if you already have the 6700 it’s kess than half the expense of my IC9100. I look forward to comparing effectiveness on the Oscars. As a lifetime AMSAT member I want to enhance the use of the birds and the Flex stuff just might be one super way to do it.

Thanks for your help

Peter
W2PP
(Edited)
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Justin - KL2D

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Hi Peter -

You are gonna love using the 6700 for AMSAT work.... it is so great to see the signal in the waterfall. You are right the transverter stuff is kinda hard to wrap your head around at first, but once you get it all configured it’s basically like having a radio that just works on those bands. The transverters become transparent to the operator, just open a slice on the desired band and go.

Good luck and hope to hear you on the birds sometime,

73
Justin
KL2D