"Karl Henrik Laache" <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- Hi group
The L-4 amp came standard with 3-400Z tubes and chimneys. The L-4B came with 3-500Z tubes and chimneys. In addition the -B included measurement of SWR. The L-4/B had axial air-flow cooling. The L-7 was another construction, more like the SB-220, without chimneys, but with the fan blowing at the side of the tubes, radial air-flow. It was delivered standard with the 3-500Z tubes. I would think that the L-7 construction was the cheaper one compared with the L-4/B with their centrifugal blower and chimneys. The chimneys in the L-7 was probably added by someone who was mis-guided, believing that the chimneys was removed. The advantage of the L-7 over the L-4/B is the added 160 + WARC coverage. I'm not sure, but I think there is a difference between the chimneys for the 3-400 and 3-500 tubes. The 500s are slightly higher than the 400s, and the chimneys for the 500s don't have the tapering at the top, where the chimneys for the 500s are cylindrical. 73's de LA1CU Karl email: [EMAIL PROTECTED] ---------------------------------------------------------------------- Submissions: [email protected] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net ----------------------------------------------------------------------
