I have received some great responses to my post. W1NR sent wonderful information on different tubes that will prove to be invaluable. Others have sent specific amps to avoid and why I should do so, a
I think its pretty hard to beat a Drake L4B for a starter amp. They were built pretty well. The only weak link in the thing is really the Power supply caps as most need replacing due to age at this t
Hi Clint, Here's a radical question for you to ponder: WHY NOT HOMEBREW YOUR OWN LINEAR AMPLIFIER? If you're serious about wanting "...to learn", you'll do just that, and in spades too! ~73~ Eddy VE3
BOOM. Hi Clint, Here's a radical question for you to ponder: WHY NOT HOMEBREW YOUR OWN LINEAR AMPLIFIER? If you're serious about wanting "...to learn", you'll do just that, and in spades too! ~73~ Ed
Hi Clint, I was afraid you'd say that...! That is a very common fallacy -- parts ARE cheap and plentiful, but you have to bide your time, and do a lot of looking UNDER the tables at the different Ham
Hi Clint, How extensive is your collection of back-issues of QST, & CQ...? Lew McCoy penned an absolute must-read article for would-be builders such as yourself in a 1970 issue of QST, entitled "The
Interesting comparison. Back in the 70s I chose an SB-220 over an L-4B because the Heath generated less TVI when driven to the same input on CW with the same exciter (Collins 32S-3). That SB-220 is s
What modifications did you make to get 1500 watts out, was it just a power supply change? Mike Interesting comparison. Back in the 70s I chose an SB-220 over an L-4B because the Heath generated less
Hi Bud, all. Lets face it the SB-220 has been the workhorse of ham radio for 30 years. It was cheap, compact and popular. However, the SB-220 was a modified cheapened up version of the L4 design. Bad
Clint, You have gotten good advice ... but a couple more thoughts Almost any amplifier is a good starting amp but be prepared to make some changes and learn from the experience. 1) The MLA-2500 is to
Is the 4-400A a good choice for something cheap to start with? There seems to be a steady stream of cheap used ones on that internet place. Chris w0ep _______________________________________________
1. Used the SSB transformer taps on CW. 2. Added a 50-watt 27-volt Zener diode in the filament center tap on CW, to reduce key-up idling current to zero. Heat-sunk the zener to one of the interior al
Could someone can tell me how much money for a pair NOS 4-400? 73! Hsu _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listin
I hesitated to reply because one negative comment can cause quite a stir. However I'll offer my suggestions as to what to buy, rather than what not to buy...and will be just as controversial. One of
And compare the bandswitch in an SB-220 with the L4B and you will see the difference. I swear the bandswitch in an R4A receiver is as heavy as an SB-220 ! And when you mistune the SB-220 and fry the
I wouldn't buy them from that internet place unless they were from someone that guaranteed them and has tested them. Most of them are sold as-is with comments like "they worked when they got pulled"
Robert, Can you elaborate on the L4 conversions? I guess I was unaware that the L-4 floated the grids. Also, the addition of the zener in the B- line. Do these modifications just provide additional s
Just ask Lou, W1QJ, how many bad bandswitches he has seen from SB-22os. My experience is 7 out of 10 SB-220's have at least one burnt contact. The amps still may work because the contacts are redunda
Whatever amp you choose, you must train yourself to always TURN THE POWER was replace NOW THAT IS SOME REAL GOOD ADVICE!!!!!!!!!!!!!!!!!!!!!!!!!!!!! _______________________________________________ Am
One of the best commercial amps ever made for the ham market is the original ten tec Titan 425. Separate power supply, compact but powerful, quiet, runs a pair of 3cx800' I have had 3 of these amps i