DEMI 2m LPDA vs transverter

Mark Erbaugh

I would like to add 2 meters to my 6700. Someone here recommended the DEMI 2m LPDA, which takes the mW output from the 6700 and amplifies it. The alternative is a transverter that takes another band output. If I go with the LPDA, I’m pretty much locked into the Flex, while a transverter would be usable on other radios. I’d appreciate comments or comparisons.

David-N5PSM

2mLDPA is the way to go.

The 6700 already has 2m......Why convert twice?

David-N5PSM

I realize I may come across a bit "flip" with my above statement,  I apologize for that,

I would also like to say that all transverters have a band pass and the gain response of the pass-band  is not flat.   I have a 6300 with a XV144 (Elecraft) and I have a 6700 with a 2mLDPA (HP version) and there is a drastic difference.  I strongly recommend the 2mLDPA for the 6700.  If you can borrow a transverter and connect it,  but also connect a seporate antenna directly to the 6700 via the other receive path (RXA or RXB) ,  you can compare the receive by opening two pan adapters.  The 6700 has 2 SCU's so you can compare them live..........

73 de N5PSM

Mark Erbaugh

Thank you for the reply. It does make sense to use the 2m capabilities built into the 6700. 

Mark Erbaugh

My DEMI 2m LPDA is hooked to my Flex 6700. Feeding it with the same antenna, signals are much lower than on my Yaesu FT-1500 FM rig. For example, one repeater about 30 miles away comes in full scale on the Yaesu, but only S4 on the Flex. Is there something I could be missing with my configuration. I purchased the remote option and have the Flex USB port configured. It seems to be working in that the DEMI comes on when I enable the USB port and switches from RX/TX with MOX. The DEMI is configured with the COMMON (one antenna).

73,
Mark

David-N5PSM

Suggestion......Take the 2mLDPA out of the circuit and compare again, Remember the 2mLDPA is only an amp and preamp,  compare the spec sheet of the 6700 2m performance to the FT-1500 specs and see what you find?    

73 de N5PSM

Mark Erbaugh

I hooked the antenna directly to the Flex 6700 and the input signal (from a repeater) went from S3 to S4. I discovered that the LNA in the LPDA was disabled. Once I enabled that (under USB port setup), the signals are much improved.

John - AI4FR

Check antenna gain. Slider on the left in SSDR.