Re: Need schematic or transistor data (for Henry SS amp)
No, they're not for feedback; these resistors are from base to ground and even from base to base, there are three, and are different types than those used in the attenuator for example, look modern;
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GGLL <nagato@...>
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#143
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Re: Censorship/Administrator
Were you always the Moderator of Topband? The RF conductivity or the DC conductivity?
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R L Measures
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#142
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Re: Censorship/Administrator
Thanks, Jim. RIP, Bill Fisher.
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R L Measures
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#140
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Re: YC-156 amp
Jim, more years ago than I can remember I built a 4-1000A GG amp. It was ok, but hard to drive. At that time I had a HT-37. I came upon a 3-1000Z, which can be plugged right into that same socket.
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Mike\(W5UC\) & Kathy\(K5MWH\) <w5uc@...>
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#139
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Re: Drake L7
I agree with Will. Why rebuild, I would just fix whats broken and continue to use it. 73 Jim SM2EKM -------------------- tm303 wrote:
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Jan Erik Holm SM2EKM
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#138
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YC-156 amp
Jim, Grid drive I suppose? In GG I would guess with 200W drive maybe 5-6 kW, or? Im planing to replace my 2x4-1000As with a YC-156, I think its a ideal tube. As soon as I can get hold of a good one at
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Jan Erik Holm SM2EKM
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#137
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Re: Censorship/Administrator
This is all I know on the matter Rich, however I suppose it could have happned in a car. 73 Jim SM2EKM ------------------------------------------------------------- R L Measures wrote:
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Jan Erik Holm SM2EKM
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#136
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Re: Need schematic or transistor data (for Henry SS amp)
Guillermo, Is the resistors in mention connected across the base and collector of each transistor? If so, someone could have been trying to add feedback to the transistors. Generally though a
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craxd <craxd1@...>
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#135
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Re: Can Grid Dissipation in metal GG triodes be increased ????
Jim, Grid dissipation is measured by ohms law, grid voltage by grid current. Since the grid is at ground, you just measure the catode voltage with a scope. For calculation of efficiency you have to
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Peter Voelpel <df3kv@...>
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#134
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Need schematic or transistor data (for Henry SS amp)
I'm searching for a solid state amplifier circuit, a Henry model C130A30 (for VHF FM). The one I have seems to have been modified, I see some resistors strangely connected both at base and collector;
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GGLL <nagato@...>
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#133
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Re: Censorship/Administrator
Wrong again Rich. I'm the moderator for Topband and I didn't boot you off...so please fabricate another story about why you voluntarily left. I thought maybe it was because you realized you didn't
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bill_w4zv <btippett@...>
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#132
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Re: "New" method of fabricating a better chimney
The straight up and down chimney will work pretty well if the flange is sub mounted below the chassis so air has a better path up through the anode. That's the plan here for the YC-156/179. 73, Tony
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Tony King - W4ZT <w4zt-060920@...>
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#131
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Re: Can Grid Dissipation in metal GG triodes be increased ????
That is a good point for tubes like the YC-156/179. On tubes like the planar constructed GS-35B, the grid is tied directly to the ring and can move more heat. Unfortunately, the actual construction of
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Tony King - W4ZT <w4zt-060920@...>
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#130
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Re: Can Grid Dissipation in metal GG triodes be increased ????
connection piece of bottleneck I would the size and have to ### The grid in both a 3000/6000/YC-243 is 225 W CCS... and resembles a bird cage. The joke is.. you can use it for a dummy load for your
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pentalab <jim.thomson@...>
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#129
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Re: "New" method of fabricating a better chimney
Peter & Jim, I started using a thick fish paper and paper tubing like that used for RF coils. You can buy it in larger diameters. I tried some with some 4CX250B's just to see how it worked and it was
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craxd <craxd1@...>
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#127
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Hipot and other equipment for sale
All, I have the following four pieces of test equipment for sale; (1) Model 1020-B Megohm Meter by Freed Transformer 1 meg to 100k meg (2) Model 404M3 "Hypot" by Associated Research 4 kV @ 100w (3)
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craxd <craxd1@...>
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#128
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Re: "New" method of fabricating a better chimney
Hi Jim, I use heatresistant glass cylinders I get made locally and also use round teflon covers as you, thats works very well. All my blowers are made by EBM. I do not like to boost a tubes rating, I
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Peter Voelpel <df3kv@...>
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#126
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Re: Fw: [Amps] Step Start on a 3KA Amp
item. by doing Seems to me like the inrush shock to the PS lasts well more than 1/180th of a second (2 crossings every full 60 Hz cycle). If their step-start uses SS zero-crossing devices, that means
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Paul Christensen
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#125
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Re: Drake L7
Tom, If the board isn't damaged (traces burnt off), I'd just repair it. I'd think that would be the cheaper way to go. First thing I'd do is to make sure the lightning didn't short out the power
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craxd <craxd1@...>
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#123
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"New" method of fabricating a better chimney
Since Eimac never made a chimney for either a 3CX-3000A7 or a 3CX-6000A7 [or the socket] several after market chimneys have appeared. I purchased the one for the 6000A7. It was solid 1/4" thick
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pentalab <jim.thomson@...>
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#124
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