[Amps] 3 dB mobile power increase

[PA3DUV]

John,

Thanks for the info.  Actually the SG500 amplifiers are both 50 ohm input and output. In the meantime I found some valuable data on the Communications Concepts wesite.

Concerning the spark plugs: In my Toyota 7 seater van, the same type of plugs are used. So far the ignition is not affected @ 600 watts out into the HiQ 5-80, but I am not shure what will happen with two SG500 amplifiers running in parallel @ 1200 watts out. The main issue will be to get a stiff DC power supply. Currently I use one 100 AH gell cell battery adjacent to the SG500, and a 1 Farad capacitor connected to the SG500 DC terminals. For the second SG500 I consider to use the same approach.
Best of luck with your 500 watt amp project, that should get your signal over the pond!

Cheers, Dick



  ----- Original Message ----- 
  From: Japerlick at aol.com 
  To: dick.knol at planet.nl 
  Sent: Thursday, February 10, 2005 10:02 PM
  Subject: Re: [Amps] 3 dB mobile power increase


  Dick

  The combiner is not difficult at  all...there are lots of books/articles/papers to do it.  You may have to have a two stage combiner, one to convert the input to two 25 ohm sources then one to sum those to a 50 Ohm output.  You probably want to check out jerry Seviks "Broadband transformer" book. He has written many articles in QST, ARRL pubs, etc.  His latest book is pretty good, low cost, adn would have plenty of ideas for you.

  Good luck with this project.  I run a 706 barefoot in my car with a HiQ 3-80.  My problem is extreme ignition noise...waiting for summer to track it down.  I have an Acura TL and it has little spark coils at each spark plug....so who knows what problems I am gonna face!  I am building a homebrew amp for my car...using 4 MRF150's and other parts cobbled from Harris amps.  It should be good for about 500 Watts output.

  John
  K0UM