- 161. [Amps] 813's.. Parasitic suppressor's (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Mon, 12 Apr 2010 03:35:19 -0700
- Somebody asked a while back abt the need for parasitic suppressors' on a GG- 813 amp. A buddy had one blow up on his 2 x 813 amp last yr.. across town. he tossed both the blown one.. and also the rem
- /archives//html/Amps/2010-04/msg00411.html (7,072 bytes)
- 162. [Amps] A tale of two IMs What happens? (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Mon, 12 Apr 2010 04:06:45 -0700
- ORIGINAL MESSAGE: REPLY: Let me take a guess on this one. I have not measured the change in IMD with reduced power, but I think this makes sense: Most amps that we use are biased for class AB1 or AB2
- /archives//html/Amps/2010-04/msg00412.html (10,405 bytes)
- 163. [Amps] HV lytic max V ratings..some notes (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Tue, 13 Apr 2010 02:15:45 -0700
- I dont see anything wrong with a 5-10% variation in the voltage across each cap in an amp with enough headroom. Individual capacity was all over the place 25-50 years ago unlike today where 20% is th
- /archives//html/Amps/2010-04/msg00443.html (9,496 bytes)
- 164. [Amps] Bill's novel idea of parasitic suppression. (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Tue, 13 Apr 2010 02:41:59 -0700
- Bill, wrt had mentioned abt using a variable cap in series with a coil, in series with a resistor, all wired between cathode and chassis, to eliminate parasitics. I think the idea of the resistor was
- /archives//html/Amps/2010-04/msg00444.html (7,391 bytes)
- 165. [Amps] HV lytic max V ratings..some notes (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Wed, 14 Apr 2010 00:37:18 -0700
- The L4PS.. and L7PS used 100 k , 2 watt carbons... and even they look ** Dentron did the same. Alpha used a pair of 220K in parallel. talking abt 120 hz ripple either. The ESSB audio sounds cleaner..
- /archives//html/Amps/2010-04/msg00451.html (12,571 bytes)
- 166. [Amps] A tale of two IMs What happens? (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Mon, 12 Apr 2010 06:04:06 -0700
- "No one has touched the question on how reducing power without returning affects IM I now have another one. Given that most of todays transceivers have an IM or roughly -35db "so I've been told", xcv
- /archives//html/Amps/2010-04/msg00456.html (15,580 bytes)
- 167. [Amps] HV lytic max V ratings..some notes (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Thu, 15 Apr 2010 02:42:04 -0700
- ** Dont know of any failure issues. Later models went with the 1N5408 as the price difference came down to almost nil. Peak rep is way too low, surge is too low. How cheap could they get ? ** Then yo
- /archives//html/Amps/2010-04/msg00466.html (13,856 bytes)
- 168. [Amps] HV lytic max V ratings..some notes (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Fri, 16 Apr 2010 06:14:59 -0700
- ** I wasnt talking about those later amps. I stay far away from microprocessor crap. palstar/Emtron. they all have 3.5 kva xfmr's in em. ** More junk to buy, find room for, and eventually blow unless
- /archives//html/Amps/2010-04/msg00477.html (11,885 bytes)
- 169. [Amps] Grounded grid matching circuit (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sat, 17 Apr 2010 01:35:47 -0700
- In the March 1978 HAM RADIO magazine, Ulrich Rohde wrote about an elliptic filter covering the amateur bands from 1.8 to 30MHz, suitable for an input circuit to an amp needing a 50 ohm to 100 ohm ste
- /archives//html/Amps/2010-04/msg00499.html (9,365 bytes)
- 170. [Amps] HV lytic max V ratings..some notes (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sat, 17 Apr 2010 02:08:58 -0700
- ** Youre starting to sound like someone we know, making up specs on the fly (-: Grab a real Dahl catalog and run the math. Example is the Commander 2500 Heavy Duty replacement is 900V @ 2A ICAS. The
- /archives//html/Amps/2010-04/msg00501.html (12,276 bytes)
- 171. [Amps] Grounded grid matching circuit (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sat, 17 Apr 2010 07:31:29 -0700
- Colin: Drive power is 100 watts to a 4PR1000 with 5000v on the anode. I (think) it will make near legal limit output with a 200 ohm resistor and a 4:1 unun. Will such an input screw up the IMD withou
- /archives//html/Amps/2010-04/msg00509.html (10,186 bytes)
- 172. [Amps] A tale of two IMs What happens? (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sun, 18 Apr 2010 03:52:31 -0700
- Not quite right: . Intermodulation products are multiplicative, not additive: if the first stage amplifier generates IM products of, say -6o dBc , a second identical amplifier will generate its own I
- /archives//html/Amps/2010-04/msg00526.html (11,467 bytes)
- 173. [Amps] Tuned inputs (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Mon, 19 Apr 2010 07:00:01 -0700
- Henry uses a broadband input for the 8K that seems to function. It is a stack of 3 ferrite toroids with Hi bands/Low bands switching. It can be purchased as an individual part. As they say, YMMV! Car
- /archives//html/Amps/2010-04/msg00558.html (7,366 bytes)
- 174. [Amps] Tuned inputs (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Mon, 19 Apr 2010 18:56:39 -0700
- And what is the operating input VSWR? I haven't heard back about the RF deck I worked on yet. Using the tube as a dummy load and with low power it was well under 2:1 on all bands. No flywheel action
- /archives//html/Amps/2010-04/msg00563.html (8,418 bytes)
- 175. [Amps] Tuned inputs (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Wed, 21 Apr 2010 03:55:04 -0700
- wierd effect from the un-un.? Both the FT1000 and IC7800 do the same thing but are fine into other non-perfectly-matched loads.? Theoretical explanation, anyone? Henry 8K/3K Ultra Operating Manual; p
- /archives//html/Amps/2010-04/msg00587.html (10,083 bytes)
- 176. [Amps] Thinking out loud (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Wed, 21 Apr 2010 22:42:05 -0700
- I already have just about all the parts for my amplifier, which will use a pair of 813's, but before I do too much construction I need to settle on the design :-) Since I only operate CW I had decide
- /archives//html/Amps/2010-04/msg00603.html (8,544 bytes)
- 177. [Amps] EBS.. does it even work with VOX SSB ?? (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Thu, 22 Apr 2010 02:50:32 -0700
- For you folks out there with EBS.. that can actually disable it, does it really save any heat ? I'm thinking primarily of VOX SSB. I can see EBS working on PTT.. but not very well, or if at all.. on
- /archives//html/Amps/2010-04/msg00604.html (7,778 bytes)
- 178. [Amps] GigaVac Relays (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Tue, 27 Apr 2010 03:25:07 -0700
- In the past year or two, there have been questions about Gigavac relays and their reliability. Up to now, I've heard no assessments one way or the other. At the Visalia DX convention last weekend, I
- /archives//html/Amps/2010-04/msg00659.html (9,346 bytes)
- 179. [Amps] plate load Z (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sun, 2 May 2010 00:46:30 -0700
- -- Yes, I agree (E / I ) / K. Mental lapse before, sorry. 73, Gerald K5GW later... Jim VE7RF _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contest
- /archives//html/Amps/2010-05/msg00007.html (6,742 bytes)
- 180. [Amps] VO Stokes Book (score: 1)
- Author: "Jim Thomson" <Jim.thom@telus.net>
- Date: Sun, 2 May 2010 00:51:33 -0700
- Thanks, all, for your advice. I tried a simple approach last night, I zipped the Stokes transmitter book in a large baggie with a quantity of sodium bicarbonate, and changed it once with fresh powder
- /archives//html/Amps/2010-05/msg00008.html (7,021 bytes)
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