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References: [ +from:Peter_Chadwick@mitel.com: 967 ]

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121. [AMPS] Fertility (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 31 Jan 2001 10:01:34 -0000; There was a case here where it was claimed that a mobile radio antenna on a water tower was radiating and making an 11 year old girl hyper-active and all the rest of the bad things. Spoilt the story; /archives//html/Amps/2001-01/msg00755.html (8,859 bytes)
122. [AMPS] Plate Transformer (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 31 Jan 2001 10:43:04 -0000; Some transformers have oil, even quite small ones. I've got one with dual 6.3 at 0.6 amp windings which is oil filled - it's rated for 5kV insulation. But oil is used for cooling.I've not come across; /archives//html/Amps/2001-01/msg00757.html (7,454 bytes)
123. [AMPS] RCA (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 31 Jan 2001 11:54:24 -0000; It's in the TT5 Transmitting Tube manual, up at the back in the 'typical applications' section as we'd call it these days. They feed back to a tertiary winding on the filament choke. I've a feeling I; /archives//html/Amps/2001-01/msg00761.html (7,967 bytes)
124. [AMPS] Fertility (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 31 Jan 2001 14:46:22 -0000; The effects of the big propellers on generators in wind farms is a matter of concern to the French, German and Dutch radio administrations because of the interference to radio - that's to fixed links; /archives//html/Amps/2001-01/msg00765.html (7,887 bytes)
125. SV: [AMPS] SB-220 Glitch Resistor ??? (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 4 Dec 2000 08:20:07 -0000; There are some opto couplers that appear in surplus sales (and are presumably still manufactured) which are designed for rotary motion sensors. These have a fairly large spacing (3/4 inch?) between d; /archives//html/Amps/2000-12/msg00056.html (8,346 bytes)
126. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 4 Dec 2000 08:42:43 -0000; I worked on a satellite ground station tx some 35 years ago. (10kW CW at 6GHz). That had a fibre optic cable looking down the waveguide towards the antenna; if an arc started because of excessive VSW; /archives//html/Amps/2000-12/msg00057.html (9,201 bytes)
127. [AMPS] KW-500 (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 4 Dec 2000 09:05:22 -0000; Vintage 1957/8 time. As I remember, has no tuned input, and only about 2.2kV on the plate- and, at least in the early versions, 866 rectifiers. Pi tank, so can handle a wide range of output loads (at; /archives//html/Amps/2000-12/msg00058.html (7,133 bytes)
128. [AMPS] Low Pass Filter (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 4 Dec 2000 09:41:44 -0000; I did some tests on cardboard tubes and wirewool, and found that the method has its uses. It's only for reducing the amount of signal on the outside of the coax, and with a 1 metre length, I could ge; /archives//html/Amps/2000-12/msg00059.html (8,011 bytes)
129. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 4 Dec 2000 09:46:38 -0000; Even when the SWR is good, that can be the best way. It certainly used to be the way that big (over 10kW) transmitters were tested professionally - you've got to dissipate the energy as heat anyway.; /archives//html/Amps/2000-12/msg00060.html (9,240 bytes)
130. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Tue, 5 Dec 2000 08:27:57 -0000; In the context we're discussing, this is very true. However, it's not a 'tablet of stone' for all RF stages everywhere under all conditions, falling down at UHF and beyond, where the time taken for b; /archives//html/Amps/2000-12/msg00070.html (9,819 bytes)
131. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Tue, 5 Dec 2000 15:55:27 -0000; At one time, most QST/handbook designs did have catching zeners on collectors. How much use they are is another matter, as zeners do take time to breakdown. BTW, is it zener or avalanche breakdown be; /archives//html/Amps/2000-12/msg00072.html (8,769 bytes)
132. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Tue, 5 Dec 2000 16:36:42 -0000; The zeners were from collector to ground, and were usually 36v zeners on a 13.6 v supply. This makes me feel very old, as I can remember semiconductor manufacturers making a big thing out of the fact; /archives//html/Amps/2000-12/msg00077.html (8,693 bytes)
133. [AMPS] SWR Protection (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 6 Dec 2000 08:17:48 -0000; As I don't do high power RF professionally (in this context, over 10milliwatts!) these days, I stick to 'hollow state' PAs at home, where the problem doesn't exist!! 73 Peter G3RZP -- FAQ on WWW: htt; /archives//html/Amps/2000-12/msg00090.html (7,825 bytes)
134. [AMPS] AL-1200 Blower (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Thu, 7 Dec 2000 13:42:44 -0000; A number of Marconi tx's for military and naval applications did that for detecting excess plate dissipation back in the late 1950's, for tx's with 4-125 and 4-250. The photocell and a 12AU7 schmitt; /archives//html/Amps/2000-12/msg00110.html (8,664 bytes)
135. [AMPS] AL-1200 Blower (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Fri, 8 Dec 2000 08:10:48 -0000; How very true. However, trips that are a plain nuisance lead to them being defeated.......and if you're in the military, I expect it's more important to keep the tx on the air than to maximise tube l; /archives//html/Amps/2000-12/msg00125.html (7,956 bytes)
136. [AMPS] Choke series resonance clarification (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Mon, 11 Dec 2000 08:45:43 -0000; Is this something to do with bridges? 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems:; /archives//html/Amps/2000-12/msg00190.html (8,677 bytes)
137. [AMPS] GU-84B Const. current curves (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Wed, 13 Dec 2000 08:59:51 -0000; The RCA data books (TT4, TT5), shows how to design RF Linear amplifiers without using constant current curves. 73 Peter G3RZP -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@conte; /archives//html/Amps/2000-12/msg00211.html (6,889 bytes)
138. [AMPS] SB220 power output (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Thu, 14 Dec 2000 08:11:28 -0000; What sort of bearings are they? I would have expected a plain bearing made from 'oilite' to do a lot better than 1000 hours between oilings. Or is it just a very cheap plain brass affair? Even at tha; /archives//html/Amps/2000-12/msg00221.html (8,115 bytes)
139. [AMPS] SB220 power output (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Thu, 14 Dec 2000 13:42:05 -0000; Then I can only say that you wouldn't make an real old fashioned AM operator, Rich, pontificating with the transmit switch locked down for overs of at least 20 minutes!!! I guess it depends on whethe; /archives//html/Amps/2000-12/msg00226.html (8,021 bytes)
140. [AMPS] A tuned line problem (score: 1): Author: Peter_Chadwick@mitel.com (Peter Chadwick); Date: Fri, 15 Dec 2000 12:24:55 -0000; I'd go for a solenoid driven system as being potentially cheaper, as probably easier. If the moving contacts were the input and output of the section, the bypass could be matched. ____ B C In-- --out; /archives//html/Amps/2000-12/msg00234.html (8,045 bytes)

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