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Total 20 documents matching your query.

1. [AMPS] chip capacitor source? (score: 1): Author: f.g.robertson@open.ac.uk (Fraser Robertson); Date: Wed, 24 May 2000 16:58:44 +0100; I need some chip capacitors for a 50 Ohm LPF following a solid state VHF power amp. Can anyone tell me where I could buy these, preferably in the UK? The amp is capable of 200W output, but is unlikel; /archives//html/Amps/2000-05/msg00272.html (6,864 bytes)
2. [AMPS] dBc and dBu ??? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 28 Jun 1999 09:33:49 +0100; Can anyone tell me what the terms dBc and dBu mean, in the context of distortion and noise performance in audio amplifiers? Would dBu mean dBmicrowatt? Many thanks, Fraser G4BJM -- FAQ on WWW: http:/; /archives//html/Amps/1999-06/msg00731.html (7,307 bytes)
3. [AMPS] dBc and dBu ??? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 28 Jun 1999 16:08:44 +0100; Thanks Jon, but not in this audio context where there is no carrier. I think it means relative to C weighted noise, but that is normally written dBrnC. I think you're right about dBu. Fraser dBc mean; /archives//html/Amps/1999-06/msg00743.html (7,769 bytes)
4. [AMPS] amp for 10-100MHz ? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 6 May 1999 09:06:26 +0100; I need to buy a linear amp for work that will deliver 50-100W between 10-100MHz, with low drive requirement, say 0dBm. I've had a few quotes but they seem on the high side to me. Even buying a module; /archives//html/Amps/1999-05/msg00090.html (6,918 bytes)
5. [AMPS] RF Power Labs - address please (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Tue, 11 May 1999 10:03:25 +0100; Can anyone give me an address or email for the above company please. Thanks / 73, Fraser G4BJM -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative req; /archives//html/Amps/1999-05/msg00133.html (6,663 bytes)
6. [AMPS] Re: Brightest & Tenth Commandment (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 24 May 1999 15:02:06 +0100; In the UK at least, the lack of soap use is not restricted to QRP enthusiasts. Some attendees of UK ham events are certainly QRO in the body odour department. 73 Fraser G4BJM -- FAQ on WWW: http://ww; /archives//html/Amps/1999-05/msg00300.html (7,792 bytes)
7. [AMPS] Band pass filter designs? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 29 Apr 1999 12:14:32 +0100; To save reinventing the wheel, can anyone point me in the direction of existing designs for HF bandpass filters to go between rig and amplifier. Presumably if the filters are built into one box, rela; /archives//html/Amps/1999-04/msg00440.html (7,688 bytes)
8. [AMPS] Properties of nylon? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 4 Mar 1999 17:03:43 -0000; Does anyone know how good an insulator nylon is, say HF up to 150MHz? Thanks, Fraser G4BJM -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative request; /archives//html/Amps/1999-03/msg00089.html (6,917 bytes)
9. [AMPS] 50 ohm 50 watt resistor... (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Wed, 3 Feb 1999 12:03:28 -0000; Meggitt Electronic Components make a range of non inductive power resistors. They are small so need to be bolted to a heatsink. I think 47R is the nearest they do to 50R, or you can parallel a pair o; /archives//html/Amps/1999-02/msg00092.html (8,358 bytes)
10. [AMPS] Drake L4B and warc bands (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 15 Feb 1999 09:13:19 -0000; I used to have one and it worked fine on the WARC bands, albeit with a higher input swr of course. 73 Fraser G4BJM Can a Drake L4B be used on the WARC bands without a modification. Thanks Will -- FAQ; /archives//html/Amps/1999-02/msg00393.html (7,987 bytes)
11. [AMPS] Re: 75 ohm cable (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 4 Jan 1999 11:15:06 -0000; Thanks for the input on this, in particular N4ZR for suggesting using a half wave length of cable (why didn't I think of that?) Over Xmas I cut myself an electrical half wave for just below topband.; /archives//html/Amps/1999-01/msg00054.html (7,038 bytes)
12. [AMPS] FT-240-61 core, where from ? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Wed, 23 Dec 1998 12:07:20 -0000; I'm looking for a UK source of these, or a suitable equivalent. Ferromagnetics (GW3TMP) no longer import them. I want them to make 50/75 Ohm 2-30MHz QRO transformers. (The design is from the 1988 ARR; /archives//html/Amps/1998-12/msg00342.html (8,410 bytes)
13. [AMPS] Fw: [TenTec] Titan info (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Tue, 10 Nov 1998 15:52:59 -0000; Using a high voltage current limited source is also common practice to increase the switching speed of stepper motor driver stages. I was taught that in the early 80's! 73 Fraser G4BJM I don't think; /archives//html/Amps/1998-11/msg00155.html (8,915 bytes)
14. [AMPS] Capacitor voltage rating? (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Mon, 12 Oct 1998 11:04:36 +0100; I am building a HF LPF to handle 150W. In a 50R system that equates to 87V rms, or 245Vpp. I have some polystyrene capacitors rated at 630V dc. Would these be ok? How do I de rate the dc voltage for; /archives//html/Amps/1998-10/msg00112.html (7,964 bytes)
15. [AMPS] Re: SSB Power Output (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 23 Jul 1998 09:24:22 +0100; I think a 50% power increase may make more difference than one would think in purely engineering terms, exactly why I don't know. I've had people tell me I've gone up three S points when I've upped t; /archives//html/Amps/1998-07/msg00155.html (8,582 bytes)
16. [AMPS] Re: SSB Power Output (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 23 Jul 1998 15:30:16 +0100; --Original Message-- From: owner-amps@contesting.com [mailto:owner-amps@contesting.com] On Behalf Of Jon Ogden Sent: 23 July 1998 14:36 To: Fraser Robertson; John Nelson; QRO reflector Subject: RE: [; /archives//html/Amps/1998-07/msg00170.html (9,870 bytes)
17. [AMPS] Yaesu Quadra VL-1000 amplifier (score: 1): Author: F.G.Robertson@open.ac.uk (Fraser Robertson); Date: Thu, 9 Apr 1998 10:44:34 +0100; Four of these amps were used on the recent 9M0C trip, and according to the write up in RSGB's April Radcom (page 44), they preformed flawlessly. 73 Fraser G4BJM -- FAQ on WWW: http://www.contesting.c; /archives//html/Amps/1998-04/msg00067.html (8,051 bytes)
18. [AMPS] more power more TVI?? (score: 1): Author: f.g.robertson@open.ac.uk (Fraser Robertson); Date: Tue, 11 Nov 1997 14:26:11 +0000; Your friend is fortunate, my experience has always been that more power = more EMC problems ! 73 Fraser G4BJM -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Adm; /archives//html/Amps/1997-11/msg00148.html (7,820 bytes)
19. [AMPS] Silver plating (score: 1): Author: f.g.robertson@open.ac.uk (Fraser Robertson); Date: Wed, 3 Sep 1997 09:27:01 +0000; Hi all, can anyone explain to me why silver plating is used to decrease loses in tank circuits and so on. Looking at the figures there seems to be a very small difference in resistivity and skin dept; /archives//html/Amps/1997-09/msg00037.html (7,976 bytes)
20. [AMPS] Silver plating (score: 1): Author: f.g.robertson@open.ac.uk (Fraser Robertson); Date: Wed, 3 Sep 1997 16:11:09 +0000; Thanks for the replies so far. I thought I was missing something somewhere, but it seems not. Mind you, I have to admit, silver plating does look the part! Fraser G4BJM -- FAQ on WWW: http://www.cont; /archives//html/Amps/1997-09/msg00044.html (7,822 bytes)

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