1. You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
    Dismiss Notice

driving a sb220

Discussion in 'Amplifiers' started by Number15, Jul 12, 2007.

  1. Number15

    Number15 Active Member

    Joined:
    May 18, 2005
    Messages:
    300
    Likes Received:
    3
    What should i drive my sb 220 with?? Please chim in Thanks.


     

  2. lords

    lords Active Member

    Joined:
    Feb 25, 2007
    Messages:
    772
    Likes Received:
    1
    well i drive mine with a brute force 350
    so the saturn 2 swinging 50 into the brute force 350 keying 150 swinging 350 into the SB220 which keys 300-500 swinging 3000

    and redone for 220volts again the 110 was blowing a AC breaker at 20amps

    don't max it over 400 into the sb220 and you will be fine
    and min is about 125 to get some good output :)

    thats just my opinion of everyday use which works great
     
  3. W5LZ

    W5LZ Crotchety Old Bastard

    Joined:
    Apr 8, 2005
    Messages:
    6,832
    Likes Received:
    759
    And without some very extensive modifications, an SB-220 will never live to see the day if will put out anything close to 3000 watts.
    "linearone" is right, something on the order of 1500 watts without more modifications than the thing would ever be worth. Bumping the input voltage to 220vac is a very good idea, makes them run 'easier'. Don't expect any appreciable increase in output power, though, ain't gonna happen. Very little of that primary voltage increase ever gets past the transformer, and what does get past would produce very large amounts of that 'magic' electrical smoke. :)
    An SB-220 was an adequate amplifier for the 'little guy' when they were new. They are not, have never, and will never be a 'big' amplifier without spending lots of money which could better be spent elsewhere.
    - 'Doc


    Some amplifier performance claims remind me a lot of that good old Redneck winter sport... Horse Hockey!
     
    n8fgb likes this.
  4. lords

    lords Active Member

    Joined:
    Feb 25, 2007
    Messages:
    772
    Likes Received:
    1
    I wouldn't say that modding it was hard.
    seeing though I do dabble in it. my CD meter shows 3000 pep
    and it wasn't big bucks either.....every day it gets used with out a problem....as for 1500 well your in the weeds :p
    and them 2 tubes can take 300 watt at a easy rate....next story!


    saying is saying
    owning and doing is doing :p
     
  5. W5LZ

    W5LZ Crotchety Old Bastard

    Joined:
    Apr 8, 2005
    Messages:
    6,832
    Likes Received:
    759
    If owning and doing is doing, then you loose. Been there done that with more than one SB-220. Without a change in primary transformer you'll never see enough plate voltage to get 3000 watts, I don't care what you drive it with. Without substituting a 'Peter Dawhl/Dahwl(sp)' transformer that won't fit into the SB-220 if you removed the tubes and RF section, forget that higher plate voltage. The standard 'HeathKit' transformer was barely adequate to start with. You can also plan on rebuilding the rectifier board, metering circuits, and find a couple of chimneys and a blower. The standard fan won't come close to being adequate, it barely is with a stock SB-220. I think I may still have a filament transformer around here somewhere, the rest of that junk hit the road a long time ago.
    The SB-220 was a pretty good 'almost legal limit' amplifier in it's day. It certainly wasn't/isn't as 'fantabulistic' as people try to make it sound like. Take a look at Rick Measure's web site. He comes closer than anyone else with most SB-220 mods. See what he has to say, then wonder about that 'talking' and 'walking' thingy...
    - 'Doc
     
    n8fgb likes this.
  6. lords

    lords Active Member

    Joined:
    Feb 25, 2007
    Messages:
    772
    Likes Received:
    1
    lol ,ya ok
     
  7. AudioShockwav

    AudioShockwav Extraterrestrial Admin
    Staff Member

    Joined:
    Apr 6, 2005
    Messages:
    5,402
    Likes Received:
    1,112
    What model meter are you using, and what slug?

    73
    Jeff
     
  8. lords

    lords Active Member

    Joined:
    Feb 25, 2007
    Messages:
    772
    Likes Received:
    1
    coaxial dynamics 83000-A
    5000 bird slug 2 to 30 MHz :) right at 2900
    and of course its a moded SB220
     
  9. W5LZ

    W5LZ Crotchety Old Bastard

    Joined:
    Apr 8, 2005
    Messages:
    6,832
    Likes Received:
    759
    and just for the hell of it, here's the URL;

    http://www.somis.org/

    Enjoy.
    - 'Doc
     
  10. lords

    lords Active Member

    Joined:
    Feb 25, 2007
    Messages:
    772
    Likes Received:
    1
    been there looked a while ago and even blew the dust off that old site......I do like there stuff but theres better...
    first the stock unit can handle and input of max 250 watts...from a
    old heath tech
    I know what your saying but a long time ago is a long time ago
    what I see and do has nothing to do with what your showing
    so on that note I will standby now :p
    I stated what I output and have no problem with what your past says...Number15 wanted to know stuff I posted...and now he knows it modded as for the transformer it has been updated along with other stuff
    also all SB220's didn't have the same transformers theres been like 3 updates back then....
     
  11. Number15

    Number15 Active Member

    Joined:
    May 18, 2005
    Messages:
    300
    Likes Received:
    3
    Thanks for the reply guys, i know a guy that uses a texas star 350v that drives a sb220 and he is getting 2700 pep on a dosy 4002 meter. I just wanted to see my options. I drive my sb220 with a palomar 200x and get about 1k out of it. Im going to try a different driver as soon as i find one LOL. Thanks #15 in Cali.
     
  12. W5LZ

    W5LZ Crotchety Old Bastard

    Joined:
    Apr 8, 2005
    Messages:
    6,832
    Likes Received:
    759
    ...and while you're looking for a different driver, you might also invest in a couple of new tubes.
    - 'Doc
     
    n8fgb likes this.
  13. Number15

    Number15 Active Member

    Joined:
    May 18, 2005
    Messages:
    300
    Likes Received:
    3
    OK LOL, my tubes are good i know what u mean but that guy i know has been driving his sb220 with a 350v for two year now and has the same tubes??? and he is a bucket mouth. Thanks for the reply.
     
  14. King Mudduck

    King Mudduck FEAR THE DUCK!

    Joined:
    May 6, 2005
    Messages:
    864
    Likes Received:
    9
    I'm with everyone else. That seems like a hell of a lot of drive to me for an SB-220!
     
  15. Captain Kilowatt

    Captain Kilowatt Professional Amateur
    Staff Member

    Joined:
    Apr 6, 2005
    Messages:
    15,120
    Likes Received:
    6,808
    Remember this is CB we are talking about. Something magical and mystical happens to amplifiers when they are operated on 27 MHz.The drive requirements go way up and the power available from the tubes goes waaaay up while distortion and IMD goes down. :roll:
     
    n8fgb likes this.

Share This Page

  • About Us

    The WorldwideDX Radio Forum was originally established in 2001. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. We are working every day to make sure our community is the best Radio Hobbyist's site.
  • Like us on Facebook

  • Premium VIP Member

    The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Care to buy us a beer? We'd really appreciate it!

    Donate to us!