Clifton Laboratories 7236 Clifton Road  Clifton VA 20124 tel: (703) 830 0368 fax: (703) 830 0711

E-mail: Jack.Smith@cliftonlaboratories.com

I've completed a suite of tests on my K2 (SN 05689) assembled by Frank, W6NEK, with and without a prototype buffer interface amplifier installed. My K2 has the following options:
- SSB option
- 100 watt power amplifier
- Noise blanker

Rather than post several dozen spectrum analyzer plots and other data points, I'll summarize the results and show an illustration or two.

The results are:
1. The buffer amplifier produces no meaningful change in the K2's performance; and
2. My K2's performance is similar to the ARRL's measured performance (better in some respects, never worse) and meets all relevant FCC rules and regulations for spurious emissions.

The following shows the main configuration for testing intermodulation and transmitted spurious and harmonics. Generally, I used an HP 8558B spectrum analyzer, with a home made A/D converter and software to capture the data in a form amenable to computer publishing.

During the tests, a prototype Z91 was connected to the buffer amplifier output and ran in normal scan mode.