Mail Archive Search: <+subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[AMPS\]\s+SWR\s+protection\s*$/>

Results:

References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[AMPS\]\s+SWR\s+protection\s*$/: 42 ]

Total 42 documents matching your query.

21. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 4 Dec 2000 01:27:54 -0500; Not true at all Bill. Let's look at a lossless system and infinite generator, since that would be the extreme. The voltage, if current goes to zero, goes to infinity. The sum of infinity and zero is; /archives//html/Amps/2000-12/msg00054.html (10,610 bytes)
22. [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)
23. [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)
24. [AMPS] SWR Protection (score: 1): Author: ccc@space.mit.edu (Chuck Counselman); Date: Mon, 4 Dec 2000 08:01:29 -0500; The radar that I mentioned also had a photomultiplier looking down the waveguide. This was Haystack Observatory's planetary radar, which (at the time) put out several hundred kW at 8 GHz, _CW_, by me; /archives//html/Amps/2000-12/msg00061.html (10,082 bytes)
25. [AMPS] SWR Protection (score: 1): Author: DAVED@ctilidar.com (Dave D'Epagnier); Date: Mon, 4 Dec 2000 09:30:32 -0700; This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --_=_NextPart_001_01C05E0F.85965040 Content-Type: text/plain St; /archives//html/Amps/2000-12/msg00062.html (18,039 bytes)
26. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 4 Dec 2000 13:58:59 -0500; Mismatches can also reduce dissipation. If the load impedance presented to the transistor increases, as a general rule dissipation decreases. The dissipation curve is almost always very lopsided, wi; /archives//html/Amps/2000-12/msg00063.html (12,188 bytes)
27. [AMPS] SWR Protection (score: 1): Author: DAVED@ctilidar.com (Dave D'Epagnier); Date: Mon, 4 Dec 2000 12:48:43 -0700; This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --_=_NextPart_001_01C05E2B.352509F0 Content-Type: text/plain; c; /archives//html/Amps/2000-12/msg00064.html (23,331 bytes)
28. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 4 Dec 2000 20:04:37 -0500; I suppose it depends on the type of operation. In SSB operation or even CW operation, I doubt the transistor is so c Many amplifiers AND rigs have that problem. Especially since many exciters bang t; /archives//html/Amps/2000-12/msg00067.html (12,750 bytes)
29. [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)
30. [AMPS] SWR Protection (score: 1): Author: DAVED@ctilidar.com (Dave D'Epagnier); Date: Tue, 5 Dec 2000 08:45:24 -0700; This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --_=_NextPart_001_01C05ED2.64BCD9C0 Content-Type: text/plain [T; /archives//html/Amps/2000-12/msg00071.html (15,210 bytes)
31. [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)
32. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 5 Dec 2000 11:01:24 -0500; If I was fooled, so was Helge Granburg at Motorola before he died. Helge, being fooled like me, thought the same thing. The reason you don't see peak voltage detection circuits is because by the tim; /archives//html/Amps/2000-12/msg00073.html (9,660 bytes)
33. [AMPS] SWR Protection (score: 1): Author: DAVED@ctilidar.com (Dave D'Epagnier); Date: Tue, 5 Dec 2000 09:07:15 -0700; This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --_=_NextPart_001_01C05ED5.724E8F70 Content-Type: text/plain Re; /archives//html/Amps/2000-12/msg00074.html (15,084 bytes)
34. [AMPS] SWR Protection (score: 1): Author: da_kang@hotmail.com (Jeff Wolf); Date: Tue, 05 Dec 2000 16:24:58; How do you plan on doing that on a wideband transformer output amplifier? Since the Impedance of the collector is equal to Collector voltage squared / twice the power output and the transformation r; /archives//html/Amps/2000-12/msg00075.html (9,342 bytes)
35. [AMPS] SWR Protection (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 5 Dec 2000 17:25:46 +0100; collectors. If we are talking about the same thing, where the zeners are, the DC path to collector, actually there's no RF voltage. The purpose of those zeners is quite different than SWR protection; /archives//html/Amps/2000-12/msg00076.html (8,852 bytes)
36. [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)
37. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 5 Dec 2000 11:39:39 -0500; SWR is totally dependent on the load impedance, not the source impedance. That's why you can change radio's or sources or tune the source all you like and SWR will remain the same. That works with a; /archives//html/Amps/2000-12/msg00078.html (8,869 bytes)
38. [AMPS] SWR Protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 5 Dec 2000 11:39:39 -0500; Most collectors have RF voltages, unless the transistors are not used in working RF power amplifiers. The Zener's mentioned certainly do clamp the peak collector voltages caused by mismatched loads.; /archives//html/Amps/2000-12/msg00079.html (8,586 bytes)
39. [AMPS] SWR Protection (score: 1): Author: w7ti@jps.net (Bill Turner); Date: Tue, 05 Dec 2000 09:18:26 -0800; ______________________________________________________ If you're talking about an open or short, I'll go along with you - but there are lots of possible faults which are intermediate between the extr; /archives//html/Amps/2000-12/msg00080.html (10,543 bytes)
40. [AMPS] SWR protection (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 5 Dec 2000 12:32:52 -0500; If the SWR is 1.3:1 and it increases to 1.7:1, both forward and reflected power will increase. A conventional detector will work fine. The only case I can think of where a conventional detector syste; /archives//html/Amps/2000-12/msg00081.html (8,110 bytes)

Current List: 21 - 40
Page: [1] [2] [3]