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A news item, "New All-Ham Crew Settles In Onboard International Space Station" [Happenings, Feb 2003, p 81] incorrectly identified one of the Expedition 6 crew members and included an outdated NASA crew photo. The correct lineup is crew commander Ken Bowersox, KD5JBP; cosmonaut Nikolai Budarin, RV3FB, and astronaut Don Pettit, KD5MDT. The accompanying NASA photograph depicted Don Thomas, KC5FVF, who had been slated to be on the Expedition 6 crew but was replaced last summer by Pettit due to an undisclosed medical issue.
The correct telephone number for Datamatrix [New Products, Feb 2003, p 107] is 800-373-6564.
In "The DBJ-1: A VHF-UHF Dual-Band J-Pole" [Feb 2003, p 40], replace "VHF" with "UHF" in the headings of Table 2, columns 1 and 2. Column 3 remains "VHF," as it refers to the use of a 2 meter VHF J-Pole on its third harmonic. Also, the area immediately to the left of the RG-174 stub should not be shaded. The decoupling stub is in series with two separate pieces of twin-lead.
In "A 222 MHz Transverter for the Yaesu FT-817," [Jan 2003, pp 31-38], the sidebar "Why dBm?" contains an error. A signal level of +12 dBm is 16 mW (actually 15.85 mW), not 13 mW, as stated. (Thanks to Dr H. Paul Shuch, N6TX, for calling this to our attention.) Power is nearly doubled every 3 dB, so +3 dBm = 2 mW; +6 dBm = 4 mW; +9 dBm = 8mW and +12 dBm = 16 mW. Or... dB (power) = 10 log [Pout / Pin], so 12 dBm = 10 log Pout/1, so Pout = log-1 (1.2) = 15.85 mW. Note that log-1 (1.2) is not the same as [log (1.2)]-1. Read this as "The number whose log10 is 1.2 = 15.85" or "10 raised to the 1.2 power = 15.85."
Also, note the following errors in Figure 3, the schematic diagram:
U4A and U4B have the pins swapped (the two sections are interchangeable); the red LED, D12, is connected to +8 V in the photo, near RY1; there are two components labeled C47 on the schematic----the one near J3 becomes C51 (0.01 µF); there are also two components labeled C48----the one near J3 becomes C50 (0.01 µF); C49 is missing from the parts list (0.01 µF), and C79 is missing from schematic (0.1 µF)----in parallel with C17.
The sentence on page 35, under the heading "The Receive Circuit," should read, "A tuned circuit, L6 and C5..."
Q2, the 2N6660, may be hard to find. The IRF510 (Digikey IRF510-ND) is a good, inexpensive substitute. Almost any N-channel power FET will work, however.
J3 clarification----the connections are to the 8-pin ACC jack on the FT-817. BANDDATA and GND go to the same pins, while PTT connects to the TX GND pin.--tnx K2QO, KA7EXM, W4YN and N9MNP
The latest corrections and updates can be found on the author's Web site.
"Amateur Radio and the Rise of SSB" [Jan 2003, p 45], states: "...vestigial sideband (VSB) has been developed for digital television." In fact, television broadcasting has been using VSB to transmit video since way back when TV first came on the air.--Ed Padget, KK5WT
