boonton 59LFcoils 电路图.pdf

file:/C|/Documents%20and%20Settings/Kenneth%20Grimm/Desktop/FOR%20BAMA/59LF-coil-construction/email.txt Hi Ken, I am forwarding the email from Alan Douglas with his measurements of the original 59LF coils, along with a picture he sent. I also attached the final configuration of my coils. My main coil values came out very close to Alans measurements, but I ended up putting the coils together, with the trim caps before measuring the final values of all the coils. Regards, -Joe - Hi Joe, Thanks for sharing the excellent photos. If you could provide a table of the inductance values, I think that the photos plus the values might make a nice addition to the 59LF collection. Thanks again, To: Joe Sousa From: Alan Douglas Subject: Re: 59LF Megacycle Meter X-Rcpt-To: Hi, Photo enclosed. This is as far as I can open the coil forms without unsoldering the wires. Coils are universal-wound on ferrite slugs 7/8 diameter, maybe an inch long. Theyre held on with wax and I cant count turns. Inductances (1 kHz) as follows, in microHenries: pins 1-2 pins 3-4 pins 3-5 A: 59, 5000, 22. B: 5.5, 900, 2.2 C: 2.8, 200, 11.6 D: 1.9, 27, * * = cant read because of 1k resistor in series. I presume you have the schematic, but pin 3 is the cold end of the coil, hot end to pin 4, tap to pin 5. Feedback winding is 1 and 2. A .1-.25MHz, B .25-.55, C .55-1.5, D 1.5-4.5. The basic coil forms are by Na-Ald (Alden), standard stuff in the 1930s and 40s. Alan www.PhilbrickArchive.org A free repository of materials from GAP/R, George A. Philbrick /Researches. Operational Amplifier Pioneer. file:/C|/Documents%20and%20Settings/Kenneth%20Grimm/Desktop/FOR%20BAMA/59LF-coil-construction/email.txt12/19/2008 10:19:50 PM RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库