Dynamic Phase Shift
Diversity Gain - Noise Cancelling
Diversity Gain - Noise Cancelling
| The front panel is fairly logically laid out, with indicators for all important functions. |
| This is the basic circuit. You are invited to modify it as required or necessary. Note that when the preamps are off, the gain controls are removed from the circuit, but the sensitivity controls remain active. Also note, the attenuator allows the adjustment of the overall output level without disturbing the relative antenna levels. The co-phase and pri/sec switches are what permits selection of which antenna will be phase controlled, and in which relationship. There are some dissimilarities between the schematic and the older panel layout. Of course, all the final details in flexibility are at the whim of the builder. Have fun with this one, and report your results for the ongoing development. |
| I have modified the original phaser schematic after the recent design updates I've researched and subsequently tested. The new circuit is shown above. This is an on-going development project, so please bear with me if you have already begun assembly. I assure you that this version is much improved in terms of functionality, effectivity, and ease of use. Caveat: (A preemptive plagiarism statement). I have many, many hours invested in the development, testing, and evaluation of this project. Some of my R&D, and subsequent testing has been based on the technology employed by the Timewave, Quantum, DX Engineering, and MFJ phasers. For good or bad, all have been evaluated to determine their technical suitability, effectivity, range of utility, and ergonomics. Still, some further development has been based on the excellent developmental work of Prof. Dr. Dallas Lankford. I make no apologies for studying the work of those who have come before me, since any good engineer should study the teachings of his/her mentor(s). Please bear with me during this process, and thank you for your support and e-mails. RWB, N1KPR - 9/30/08 |
Further
development is
indicated, but the
basic circuit
probably will not
change, although I
am currently
playing with
transformer
summing of both
phase segments
through a dual
primary torroid,
rather than the
Balance pot shown.
At this point, the L
and C values are
002Mf and 5uH.
NOTE:
Lankford's version has
a "band-switched"
configuration that I'm
sure is very effective.
development is
indicated, but the
basic circuit
probably will not
change, although I
am currently
playing with
transformer
summing of both
phase segments
through a dual
primary torroid,
rather than the
Balance pot shown.
At this point, the L
and C values are
002Mf and 5uH.
NOTE:
Lankford's version has
a "band-switched"
configuration that I'm
sure is very effective.
Updated Oct 19, '08
These preamps may be inserted ahead of
the "Balance" switch, if desired.
I use MAR-series MMIC devices
(Minicircuits), but there are many other
preamp configurations using low noise, high
dynamic range devices.
Search the Internet for <RF Preamp>.
the "Balance" switch, if desired.
I use MAR-series MMIC devices
(Minicircuits), but there are many other
preamp configurations using low noise, high
dynamic range devices.
Search the Internet for <RF Preamp>.