Remember me asking about multi-tube amps? Well, a local Ham has a brother who likes to buy, try, & sell Ham gear and he just happened to have an Ameritron 811H in need of a new home. His asking price
What does he mean, 'warms up'? 73 Tom W7WHY Well, a local Ham has a brother who likes to buy, try, & sell Ham gear and he just happened to have an Ameritron 811H in need of a new home. His asking pri
The slow start relay circuit is kaput. Alek VK6APK Well, a local Ham has a brother who likes to buy, try, & sell Ham gear and he just happened to have an Ameritron 811H in need of a new home. His ask
I have an AL-811H and there is no start circuit. It comes on when you flip the 'on' switch. From the plug there is fuse, interlock, and on/off switch. That is why I wondered what he meant when he sai
Yeah. Well that is strange. Blowed if I know what he means then. Thanks Alek. VK6APK That is why I wondered what he meant when he said 'warms up'. 73 Tom W7WHY Alek VK6APK Well, a local Ham has a bro
Yeah. Well that is strange. Blowed if I know what he means then. Thanks Alek. VK6APK warm up, the fils...or the B+ ?? I think the xfmr in the 811 has the fil winding built into the plate xfmr. It cou
You said it in one Jim. If you buy a AL811, you deserve what you get. A guy local to me had two of them. One with three tubes and one with four. They were forever breaking down and he usually brought
What was breaking down? The 811 is a good tube but most hams believe the mfrs claims and run them way beyond their ratings. 73, Roger If you buy a AL811, you deserve what you get. A guy local to me h
Those amps have had a lot of poor contact socket problems and Id take the cover off and watch the filaments and see if they are instantly on and stay on. The HV is monitored on the meter and should b
Last time I looked the Chinese rated it at 1250V; when they reach the rest of the world the sellers and amp manufacturers rate them as a 1950's era RCA. Then some make believe engineer blames the tub
From memory: The plastic encapsulated output relay on the 3 holer, totally fused on 4 occasions. The little diode in the bias/metering circuit, 3 times. The filament voltage is 10% high on both model
The seller just wrote this: "I think the problem is in the meter circuit. Even when the meter shows just 800 volt the amp does 600 watts. We were checking it out today and I don't think it needs caps
If that's the case, it would need to be a really bad switch since only 1 mA passes through it and the meter. More likely a multiplier resistor that drifted high. -WB2WIK The seller just wrote this: "
All good points you make here Alek. Apart from the el-cheapo design and construction economies made in the entry level Ameritron AL-811 series amps, the 811A was indeed a good tube, as was the 572B/1
-- ORIGINAL MESSAGE --(may be snipped) REPLY: It bothers me to see hams wasting their time and money on tubes made of glass. This is an obsolete technology which is of historical interest but really
Personally I wholeheartedly concur with your sentiments here Bill; most of my shack amps are of the ceramic tube variety and indeed do seem to last forever. My only exception amp is the venerable Ken
Author: Louis Parascondola via Amps <amps@contesting.com>
Date: Fri, 23 Jan 2015 21:24:14 -0500
Bill, 3-500 tubes are pretty good, but I agree, 811 tubes are light duty. --Original Message-- From: Bill Turner <dezrat@outlook.com> To: Amps group <amps@contesting.com> Sent: Fri, Jan 23, 2015 9:07
Glass is simply a transparent ceramic. Well... More or less, anyway. Nothing wrong with that as long as the limitations are respected. Kim N5OP Consequently a matched pair or quad set of reputable br
-- ORIGINAL MESSAGE --(may be snipped) Consequently a matched pair or quad set of reputable brand vintage NOS 811A / 572B tubes are worth their weight in gold....and highly sought after. REPLY: It b
-- ORIGINAL MESSAGE --(may be snipped) REPLY: Actually, there is a fundamental difference. Glass is a supercooled non-crystalline liquid, whereas ceramic has a rigid crystalline or partly crystalline