ARRL Members can now download the October, 2004 QST Product Review
column online in PDF format. The first product reviewed is the Elecraft
XV144 transverter kit - a 20W 144 MHz transverter for a 28 MHz IF rig.
http://www.arrl.org/members-only/prodrev/pdf/pr0410.pdf
Some lab numbers in brief:
Conversion gain: 24 dB
Noise figure: 1.0 dB
Image rejection: 70 dB
TOI: +17 dBm
Spurious and harmonic suppression: 64 dB
Third-order two-tone IMD products: -30 dB
Fifth-order two-tone IMD products: -44 dB
The closest ARRL product review of a 144 MHz transverter is the
SSB Electronics LT2S MKII, reviewd in November, 1997
(http://www.arrl.org/members-only/prodrev/pdf/pr9711.pdf):
Conversion gain: 21.3 dB
Noise figure: 1.0 dB
Image rejection: not tested
TOI: +18.4 dBm
Spurious and harmonic suppression: > 68 dB
Third-order two-tone IMD products: -32 dB
Fifth-order two-tone IMD products: -46 dB
In June, 2000, the ARRL reviewed the Ten-Tec 1210 transverter
(http://www.arrl.org/members-only/prodrev/pdf/pr0006.pdf):
Conversion gain: 19 dB
Noise figure: 7.6 dB
Image rejection: 90 dB
TOI: not tested
Spurious and harmonic suppression: 58 dB
Third-order two-tone IMD products: not tested
Fifth-order two-tone IMD products: not tested
The closest ARRL product review match of a DEMI transverter is the
DEMI 50-28CK (http://www.arrl.org/members-only/prodrev/pdf/pr9702.pdf)
from 1997. The ARRL has never reviewed the DEMI 144-28CK. This
review was pretty harsh, as the transverter as designed required
significant external filtering to meet FCC transmit spectral purity
requirements, which also adversely affected the receiver performance.
Some numbers on the DEMI 50-28CK transverter to compare:
Conversion gain: 15 dB
Noise figure: 3.6 dB
Image rejection: not tested
TOI: not tested
Spurious and harmonic suppression: 55 dB
Third-order two-tone IMD products: not tested
Fifth-order two-tone IMD products: not tested
--
Kenneth E. Harker WM5R
kenharker@kenharker.com
http://www.kenharker.com/
_______________________________________________
VHFcontesting mailing list
VHFcontesting@contesting.com
http://lists.contesting.com/mailman/listinfo/vhfcontesting
|