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Several readers questioned the Blocking Gain Compression and IMD Dynamic Range test results reported in Table 1 of the Product Review of the ICOM IC-7700 [Oct 2008, pp 41-47]. The review transceiver was no longer available for testing, but here are results from another IC-7700, s/n 0201390. At 14 MHz, 500 Hz bandwidth:

Noise floor (MDS), preamp off/1/2     –126/–138/–142 dBm

Blocking Gain Compression
   20 kHz spacing, preamp off/1/2       133/139/132 dB
   5/2 kHz spacing, preamp off            120/108 dB

Two Tone IMD Dynamic Range
   20 kHz spacing, preamp off/1/2       104/108/104 dB
   5/2 kHz spacing, preamp off            99/87 dB

Compared with the results shown in the review, the Blocking Gain Compression numbers are significantly higher. IMD Dynamic Range numbers are somewhat lower. The modified data table is included at the end of the IC-7700 Product Review on the ARRL members Web page.

In “Where is Bob?” [Apr 2009, pp 51-53] the author’s reference to the programming language should be spelled PERL, an acronym for practical extraction and reporting language. For more information, including a version that will run on most operating systems, see www.perl.org.

In Figure 5 of “Superior Audio from a $5 Boom Arm Mic” [Apr 2009, pp 78-80] the negative side of the battery should be shown connected to the shield of the cable going to the electret mic element.