[Drakelist] L4/L4B/L7 power transformer
Does anyone need a power supply transformer for these amps? Let me know. Lou___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[drakelist] L4-L4B-L7
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:drakelist@www.zerobeat.net 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 --
Re: [drakelist] L4-L4B-L7
danny [EMAIL PROTECTED] made an utterance to the drakelist gang -- Thanks Karl.. Your posting is correct...glad someone knows how is is Danny...WA4SDE.A Drake lover for over 30 years. - Original Message - From: Karl Henrik Laache [EMAIL PROTECTED] To: drakelist@www.zerobeat.net Sent: Thursday, January 12, 2006 3:45 AM Subject: [drakelist] L4-L4B-L7 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:drakelist@www.zerobeat.net 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 -- -- Submissions:drakelist@www.zerobeat.net 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 --
Re: [drakelist] L4-L4B-L7
[EMAIL PROTECTED] made an utterance to the drakelist gang -- On Thu, 12 Jan 2006, Karl Henrik Laache wrote: 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. 3-400Z chimneys are a half inch shorter than 3-500Z chimneys. I have a pair of 3-400Z chimneys for sale, btw. Anyone interested, please email me - I can send photos when I get home after work. Eimac 3-400Z and 3-500Z chimneys have the tapered top to provide airflow over the anode seal and heat dissipator. 3rd party chimneys have a relatively small taper and don't do such a good job to cool the anode seal. Coleman lantern glass is cylindrical (has no tapered top) and is useless to protect the anode seal. Glass chimneys sold by Ameritron for 3-500Z tubes will not work with 3-400Z tubes in the Drake L-4 - they're too tall. You can get a rough idea of the form factor of the SK-416 inside my L4 by viewing these links: http://n1su.com/tubes/3-400Z-idle.jpg http://n1su.com/tubes/3-400Z-bias.JPG As discussed at length on the Amps mailing list, the chimney system used in the Drake L-4/L-4B does a poor job of protecting tube life - the only way to improve it without major modifications is to replace the stock fan with one that provides increased air flow - but the bottom line is it still doesn't provide a safe environment for exceeding the original design: 1000W input for CW and 2000W input for SSB. -- 73 Jason N1SU http://n1su.com/ -- Submissions:drakelist@www.zerobeat.net 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 --
