[AMRadio] 4-400 first made when?
In doing some research - I notice that the 4-400 seems to be a fairly late arrival, at least as far as RCA is concerned. It's in none of my HB-3s, not in my 1962 TT5, but is in the 1975 TT5 manual. Since my transmitting tube library has this 12-year gap, I'm assuming RCA began to produce the device sometime after 1964... does anyone have better info on the history and development of this very 'popular' power tube? Thanks in advance for any enlightenment! Okay - over and out... Cheers John KB6SCO DM09fg __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] 4-400 first made when?
I've not researched the 4-400, but I can say for sure we replaced the 4-125's with 4-400's when we upgraded our broadcast transmitter from .25kw to 1kw around 1961. The transmitter was a Collins, 20J and the upgrade made it a 20V-2. 73 de W4MIL Chuck -Original Message- From: [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Fri, 23 Mar 2007 11:16 AM Subject: [AMRadio] 4-400 first made when? In doing some research - I notice that the 4-400 seems to be a fairly late arrival, at least as far as RCA is concerned. It's in none of my HB-3s, not in my 1962 TT5, but is in the 1975 TT5 manual. Since my transmitting tube library has this 12-year gap, I'm assuming RCA began to produce the device sometime after 1964... does anyone have better info on the history and development of this very 'popular' power tube? Thanks in advance for any enlightenment! Okay - over and out... Cheers John KB6SCO DM09fg __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. AOL now offers free email to everyone. Find out more about what's free from AOL at AOL.com. __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] 4-400 first made when?
- Original Message - From: John Lawson [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Friday, March 23, 2007 7:16 AM Subject: [AMRadio] 4-400 first made when? In doing some research - I notice that the 4-400 seems to be a fairly late arrival, at least as far as RCA is concerned. It's in none of my HB-3s, not in my 1962 TT5, but is in the 1975 TT5 manual. Since my transmitting tube library has this 12-year gap, I'm assuming RCA began to produce the device sometime after 1964... does anyone have better info on the history and development of this very 'popular' power tube? Thanks in advance for any enlightenment! Okay - over and out... Cheers John KB6SCO DM09fg Hi John, Eimac, known then as Eitel-McCullough, as well as a number of other tube manufactures faced a dilemma at the end of WWII. Millions of tubes had been manufactured and were glutting the market. Tube manufactures, who had a good run during the war, faced a consumer market when the war ended. With all the surplus tubes available they had to develop a new market to survive. That is why (and when) the air-cooled tube family of power tubes was introduced. 4-65, 4-250, 4-400, 4-1000 were only some of the models of the new designs. Unfortunately, some companies, such as Heinz and Kaufman were trapped by accepting late contracts from the military. The contracts kept the business alive for a short time after the war ended, but when the contracts ran out, HK found themselves out of the consumer market. They never could catch up. Bill __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] 4-400 first made when?
Brad and the group, My posting said 20Jno such animal to my knowledge. My age is allowing the thoughts of the 20V2 and the 300J to run together. I should have said, the transmitter was a Collins 300J and the upgrade made it a 20V-2. Now I feel better. I'm reasonably sure we changed some iron but thats been a long time ago. We did add a Rube Goldberg designed homebrew solenoid arrangement that allowed use of the power cutback switch. The station ran 1kw day, and .25kw night. The transmitter was remotely controlled and if I remember correctly, the R/C unit was made by RUST, Corp.. I'd suggest getting a schematic of the 20V-2 and comparing it with the 300J to make your restoration a bit easier. Funny, I can still remember the Ep , Ip and I (ant) plus the antenna resistance. 1500v, .225a, .73a and 470 ohms. (.25kw readings) For the 1kw power setting they were 3100v, .455ma, 1.49a and 470 ohms. I must have read those meters hundreds of times. We were always wary of an FCC visit. And we had one or two while I was CE. Those were the days. Brad, if you were close by I'd volunteer to assist in bringing the old transmitter back to life. They were excellent pieces of gear. Gud luck es 73 Chuck W4MIL -Original Message- From: [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Fri, 23 Mar 2007 1:44 PM Subject: RE: [AMRadio] 4-400 first made when? I've not researched the 4-400, but I can say for sure we replaced the 4-125's with 4-400's when we upgraded our broadcast transmitter from .25kw to 1kw around 1961. The transmitter was a Collins, 20J and the upgrade made it a 20V-2. 73 de W4MIL Chuck Chuck, and the rest of the group, I have a Collins 300 J basket case (no iron) I am changing it to a 20V2, any advice on the 4- 400 swap, does anyone have any of the transformers, (does not have to be out of a Collins 20v2, just needs to be for 4-400's) Thanks Brad KB7FQR -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 268.18.17/730 - Release Date: 3/22/2007 7:44 AM __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. AOL now offers free email to everyone. Find out more about what's free from AOL at AOL.com. __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
Re: [AMRadio] 4-400 first made when?
- Original Message - From: [EMAIL PROTECTED] To: amradio@mailman.qth.net Sent: Friday, March 23, 2007 1:09 PM Subject: Re: [AMRadio] 4-400 first made when? Brad and the group, My posting said 20Jno such animal to my knowledge. My age is allowing the thoughts of the 20V2 and the 300J to run together. I should have said, the transmitter was a Collins 300J and the upgrade made it a 20V-2. Now I feel better. I'm reasonably sure we changed some iron but thats been a long time ago. We did add a Rube Goldberg designed homebrew solenoid arrangement that allowed use of the power cutback switch. The station ran 1kw day, and .25kw night. The transmitter was remotely controlled and if I remember correctly, the R/C unit was made by RUST, Corp.. I'd suggest getting a schematic of the 20V-2 and comparing it with the 300J to make your restoration a bit easier. Funny, I can still remember the Ep , Ip and I (ant) plus the antenna resistance. 1500v, .225a, .73a and 470 ohms. (.25kw readings) For the 1kw power setting they were 3100v, .455ma, 1.49a and 470 ohms. I must have read those meters hundreds of times. We were always wary of an FCC visit. And we had one or two while I was CE. Those were the days. Brad, if you were close by I'd volunteer to assist in bringing the old transmitter back to life. They were excellent pieces of gear. Gud luck es 73 Chuck W4MIL It is funny.. I have a terrible memory for names, can't remember a name 3 seconds after I have heard it. But the 550A-1 meter readings (3870 KHz) are, from memory: Ep, Ip, I(ant) and antenna resistance: 2000v, .225a, 2.6a and 50 ohms (375 watt reading). For the 1kw power setting they are 3000v, .500a (nominal), 4.9a and 50 ohms (1kw). Naturally, the transmitter is run at the 375 watt level. They are excellent transmitters. Interestingly, the transmitter runs with filaments on most of the time it is on at all, but the 4-400's have actually improved with use. They were 80%'ers but now put out better than full power. Guess they like Amateur AM service. If I keep running them, think they'll reach 130%? ;-) 73 de Bill, ab6mt [EMAIL PROTECTED] __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
[AMRadio] 4-400 first made when?
To All, Looking at an old 1958 ARRL handbook, the 4-400A is listed in the tube data pages. Can't go back further. This is the oldest in the library, besides I was but a mere lad at that date. 73's wd8kdg Craig __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
RE: [AMRadio] 4-400 first made when?
Good idea, Craig. However, what I'd like to know is when did RCA start making them? 73, Rick/K5IZ To All, Looking at an old 1958 ARRL handbook, the 4-400A is listed in the tube data pages. Can't go back further. This is the oldest in the library, besides I was but a mere lad at that date. 73's wd8kdg Craig __ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
