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  1. S

    45w into one 2879

    These are impressive numbers that were commonly achieved with the original part.
  2. S

    Needing help with a galaxy 1000 amplifier

    Another alternative us to just figure out which plate is bent and bend it back. If it's burnt and melted, use needle nose pliers to remove the plate it hits on the rotor side. As long as the amp tunes before the load cap is fully meshed, the missing plate didn't mater and it's removal will make...
  3. S

    Texas Star dx350 RF Choke -Value and source

    I believe that's 10 Micro Henry's at 500 miliamps.
  4. S

    3cpx1500a7

    I have no doubt the amplifier does the numbers you say and more. However, you can achieve longer tube life on an oxide coated cathode, by not undervolting the filament. This is because this type of cathode is dependent on reaching a high enough temperature to produce a protective Cloud over the...
  5. S

    3cpx1500a7

    If you can get the Chinese 3CPX1500A7 for reasonably less than you can get an Eimac 3CX1500A7, I might go for it. The reason is the higher breakdown voltages are exactly what this tube benefits from in terms of reliability. This tube is noted for grid arcs and arcing between the cathode and...
  6. S

    ICOM IC-PW2 HF/50 MHz ALL Band 1 kW Linear Amplifier

    If it's anything like the first version, Icom had zero ability to supply their authorized facilities with a single power supply component for the PW-1. If you couldn't Source the part from another supplier, you had to purchase a new Supply at approximately half the cost of the amplifier. The...
  7. S

    Looking for a Tube tester.

    This is correct. I took the base off a 811 tube to repurpose the socket. Soldered three wires into the sockets filament and grid pins. These wires attach to a 3-500Z socket that has an outboard filament transformer to run the tube. As I recall I am using the 811A test and adjusted the load for...
  8. S

    Looking for a Tube tester.

    Is the tube cracked? If not, it's likely not making a good connection in the socket. The M2057 is exceptionally difficult to find and I've never seen a tube tester with it listed. Although you can test them as a 6KD6, with the filament set for 12 volts. It's worth mentioning the M2057 tube has...
  9. S

    Base New sirio gain master 5/8 improvements ?

    This reinforcing clamp only limits flexing at the antennas first coupling joint. The weakest link, where any flex would be undesirable and cause the top of the fiberglass tube to split. It's not long enough to remove flex in the sections above or below the coupling joint. Had the new...
  10. S

    Maco 300 pumpkin face 1 driving 4 8950 Problems with red plating and have to constantly retune after one minute of no keying

    I've seen that happen with a few of the old red door knobs that they used in Heath kits. There're not as good as the tan colored ceramic ones. I'm sure they didn't use anything quite as good here either. Not that it's required.
  11. S

    Maco 300 pumpkin face 1 driving 4 8950 Problems with red plating and have to constantly retune after one minute of no keying

    "Constantly needing retuning after a minute of no keying", sounds like a fixed value capacitor across the tune or load, is shifting in value as it heats. Not even sure if there is one padding that variable, but it is one of the few things that cause that symptom.
  12. S

    TX Star 250 dx SWR ? (Something lost it's value ?)

    You're not going to like the answer. Your amplifier is oscillating. That is a typical problem with smaller Texas Star amplifiers, due to their bias circuit design, sharing an RF contact on the relay.
  13. S

    Lets talk about replacements for 6lf6 tubes

    No, in fact I've seen one brand like RCA, produce both the single and double versions.
  14. S

    Lets talk about replacements for 6lf6 tubes

    Those 3 amps of filament current, also give the 6KN6, a whooping 1.5 amps of peak cathode current! It has the widest oxide coated cathode of any sweep tube. I bought sleeves of these tubes years ago for $4.99 per tube. I've been using them ever since in every application from a single tube grid...
  15. S

    Either amazon transistors suck, or I am an idiot...

    I think the problem has to do with the DC biasing on your first single-ended transistor driver. Since it is single-ended and NPN, I don't think it should be powered from the same split rail Supply that is feeding the complementary symmetry outputs. If I suspect what is happening is correct, your...
  16. S

    What's inside a 4CX250B tube?

    Not a good idea to crack that BEO ceramic insulator. Any dust particles from the cracked insulator, are highly toxic if inhaled.
  17. S

    High Voltage hijinks, National NCL2000 style.

    With sockets changed and bias reset, it's not hard to get this amp to run inexpensive 4X150A / 7034 tubes. About $50 each for NOS. Even though this version of the tube has 150 watts less dissipation than the 8122, the anode radiator is the same size and there is no noticeable drop in output...
  18. S

    Stryker sr-94hpc

    You'll need a real peek reading watt meter in order to see the 45 watts PEP. Output power is not the problem with that radio. Being able to receive anything through the noise in the mobile environment, is the problem. The radio has no noise blanker, just a mislabeled automatic noise limiter.
  19. S

    Golden Falcon Base Amp - 10 tube

    Use a volt and ohm meter, to start checking for filament voltage and open filaments in the tubes.
  20. S

    FrankenMaco, back from the undead.

    I've been testing everything from 4CX250B, to 8877 on and old Precision tube tester, with an external socket board and a 15 amp filament Transformer. With a bigger filament Transformer, you can test a 10,000 tube. All that's required is a known good tube, to determine the correct load value. If...