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tube fanatic

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Posts posted by tube fanatic

  1. 6 hours ago, Full Range said:

    Unique dance style with extreme precision 

     

    Must watch to be amazed 

     

     


    If you want to see precision, check this out.  All the performers are deaf!

     

    Maynard

     

     

    • Like 4
    • Thanks 1
  2. 1 hour ago, CCG said:

    I had a talk with him a while back. He's from canada and getting supplies from china per order. To make it short, the deal is, its a brand new or newly assembled, 48 business days to get here, no return even if DOA. Yes that's very clear and exactly what I was told. Its like I gave him the money for a new product, he pockets it and whatever I get, that's what I get. Bottom line is, I still need a tester. I cannot rely on matched tubes. I have so much experience encountering surprises even from some suppose to be reputable US dealers. 


    I assume you want to match tubes for push-pull operation.  If that is the case they need to be matched using a curve tracer to ensure proper balance under signal conditions.  In my opinion and experience that is the only way to go if that is important to you. Whether you will be able to hear much difference is for you to judge.  You can get some insight about this here:

     

    http://aeaaudio.com/matching-tubes-with-a-curve-tracer/

     

    Maynard

     

     

    • Like 2
  3. 4 hours ago, Dave1291 said:

    @tube fanatic gonna share one with you and the posse in here.  I met this fairly local guy 30 years ago when he was just starting his ministry.  He reached out and I was there for him.  Pipes?  The big man hit the high notes HARD nailing everything he threw out there so I stepped up.  He was pullin the high notes outta his toes.  He's doing his ministry thing and still kickin so I thought I'd share.  He still sends me his cd's but his old ones were truly amazing :)

     

     

     

    :)  


     

    Very nice Dave!  Thanks for posting it!

     

    Maynard

    • Like 1
    • Thanks 1
  4. On 5/21/2023 at 6:11 PM, Mark51 said:

    I just assembled a SE 6V6 tube amp with Edcor output transformers with an 8 ohm output.  I chose 8 ohms because that's what the specified impedance was in the early literature for the Forte 1.  But now I see that it says 4 ohms on the back of the speaker at the terminals.  I never noticed that before.  And the Forte's are kinda bright and bass shy on the 8 ohm tap.  Edcor only lets you choose one output impedance which kinda stinks.  Do I have any solution other than to order new transformers?  


    Is this a SEP, or is the 6V6 triode strapped?  If you post the schematic it should be easy to come up with a solution.

     

    Maynard

    • Like 1
  5. 13 minutes ago, Travis In Austin said:

     

    W6IYD was my dad, he got his unlimited Class A in high school, I think he was 15. He got his 2nd class radio after he graduated from high school.
     

    He had those cards printed up which I guess was a big thing back in that day because there are 100s on eBay?
     

    I assuming the communication was by Morse code, not voice? These cards were exchanged to verify things like signal strength, the Transmitter power of signal being received? 
     

     


    Sorry about the confusion of the call signs.  In this instance,  the contact was with voice (“phone”).   Yes, QSL cards were exchanged and used as proof of contacts with states, provinces, countries, etc.  They were also needed as proof for the abundant awards which existed.  So, if this is your dad’s card which he sent to the ham in Minnesota, how did your dad get it back?

     

    Maynard

  6. 7 hours ago, Travis In Austin said:

    This was my Dad’s call sign, he would have been a senior in high school at this time. 
     

    Can someone explain what all of this means on this post card?

     

    B59E33D8-0BB5-457B-8672-0671F06D4492.thumb.png.c111b391780a5782be8852b069a554e6.png2A003681-16DB-4C68-86BC-18A94F91BE8B.thumb.png.7ce8bd14000ec465617b9499351df0be.png


    Not difficult to interpret:  W6IYD is the guy your dad spoke with.  QSO is a conversation with the date and time specified (on 28 mHz voice in this case). The signal report of 59 can be interpreted from this:  http://www.acsu.buffalo.edu/~maxwell/RSTInfo.html

     

    The guy’s transmitter used push pull 807s to produce 70 watts, and his receiver was a converted military surplus unit (very popular and readily available after the war).

     

    http://www.tuberadio.com/robinson/museum/command/

     

    Hope this helps!

     

    Maynard

     

     

    • Thanks 1
  7. On 4/26/2023 at 2:01 PM, JohnA said:

    Cool!  I only have an HT, for now, and am finding more local repeater all the time.  We have over 30 repeaters in the area.  With so many, few are active.  The 8 or 10 GMRS repeaters are much more active. 

     

    I've already figured out an HF antenna will not work on my tiny lot, plus, no one else in the subdivision has an external antenna.  I have a CB antenna with sloping radials in the attic that works great.  The GRMS antenna up there, not so much.  I'm looking at a 6m/2m/70cm Comet, but it is over 8' tall plus tower.  Any suggestions are welcome.  The primary objective for 6m will be talking to the Nashville area. 


    Wire antennas can be extremely effective, and can easily be arranged for HF on small lots.  You can get some ideas here:

     

    https://www.qsl.net/va3iul/Antenna/Wire Antennas for Ham Radio/Wire_antennas_for_ham_radio.htm

     

    I spent my youth under the tutelage of “old timers” who knew more electronics than the EEs in many cases, and I was involved in countless antenna projects.  
     

    Maynard

  8. 19 hours ago, mikebse2a3 said:

     

    I would disagree since it is the power supply(which obviously includes the rectifier) that we are modulating (regardless of the amplifier’s design type) and the power supply performance is an important part of the quality of the amplifiers output signal.

     

    miketn🙂


    Yes, if we are talking about the filter section of a power supply I would agree with you.  
     

    11 hours ago, Idontknow said:

     

    I've always known that it's out of the signal path, but there is a pretty overwhelming amount of reviews and claims that rectifiers can change sound. 

     

    In audio one can find claims about anything.  There are some who claim that the color of the insulation on wires has a profound effect on the sound!  The bottom line is do whatever makes you happy and just enjoy the music!

     

    Maynard

    • Like 1
  9. 14 hours ago, Idontknow said:

    Does anybody know how a rectifier can do this? I just don't understand it other than what I'm hearing. It's baffling to me. 

     


    In my opinion it can’t!  If you read the description about the percent improvement in sound it is obvious that it is all hype.  A rectifier is not in the signal path.  Its job is to provide the circuit with the voltage required for the tubes to operate within their design parameters.  If it does that, especially in a preamp with a near constant current draw, all is well.  There are all sorts of claims out there about rectifiers such as the size and shape of a getter affecting the sound.  About the only thing this device may possibly do is to ensure a constant voltage under very variable current draw conditions (such as those encountered in very high power push pull power amps).  But I would have to see the schematic of the device and real world measurements to be convinced.

     

    http://www.thebestamp.com/Accessories/Super_Rectifiers.php

     

    Maynard

     


     

    • Like 1
  10. 10 hours ago, John N. Lumley said:

    Hi again, here's current NOS tube prices at https://vacuumtubesinc.com/

    A reliable seller in Orlando, Florida, USA, that I've used for many years.

     

    6SJ7         $7.50 ea.

    6Y6GT      $3.50 ea.

    6W4GT     $3.00 ea.

     

    Rgds, <JNL>


     

    I totally agree that Jim Cross, the owner, is honest and reliable.  I have bought all my tubes from him for more years than I can remember.   
     

    Maynard

  11. 17 hours ago, John N. Lumley said:

    If there's enough interest, I could supply CNC machined Hammond 6X9X2" aluminum mono-block chassis (as used by Maynard

    Rgds, <JNL>

    IMG_2667-1.jpg.a7ab83250262384b68ec908a30daa4a6.jpg


     

    That is a wonderful offer John.  I used the 9x7 chassis which allows ample room for maneuvering underneath.  One of the biggest deterrents for prospective diy-ers is the chassis prep.  I hope you get lots of interest!

     

    Maynard

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