Thanks for the look inside! To clarify on the power capability, I see in the Matchbox documentation that that 275 W is -- just as we rated ham transmitter power in those days -- _input_ power, not output. Assuming 70% efficiency -- pretty optimistic :-) -- that equates to 193 W output. So saying that it's a "200-W" tuner is fine, but 275 W _output_ would be beyond its ratings. On a hunch I checked the maximum input power of Johnson's mid-range transmitter of those days, the Viking Valiant. Sure enough, the Valiant was rated at 200 W input AM, 275 W input CW. So the (non-kilowatt) Matchbox was designed to handle the output power of the Valiant. Best regards, Dave/W9BRD
This is "AM" rated and the PEP equivalent of 200 watts is 800 watts PEP (in AM Mode). especially in digital modes or SSB, it's good for more than 500 watts continuous (non-AM) operation.
Awesome old tuner. I got mine with a johnson viking ll and a hallicrafters sx 71 rxer. My tuner is different as it has a meter and two knobs up at the top. I also got an external vfo with the viking. ;-) all for 100.00
Eric 12374 Sound like you have a nice old ham radio system. I also have SX71 but no Viking 2 - I do have the old ThunderBolt amp and driver. Don't think I will ever put them in service. dave www.n4usa.com
We are located in Floyd Virginia - the heart of the Blue Ridge Mountains and 6 miles West of the Blue Ridge Mountains. The LCF Group has available for the public a community amateur radio station N4USA and a Historical Microcomputer Museum. We welcome you to come by for a visit. The LCF Group also keeps lots festivals & events going at our Chantilly Farm We have annual Bluegrass festival ever in May on Memorial Day . A beautiful special event hamradio station N4USA at farm also -Dave KK4WW
Paulobraveheart ios Hi - It depends on the antenna if a match box would be needed. The Match Box is a very old tuner you would want a more modern tuner like an MFJ product or similar. Dave
Hi Thank you for the comment. I look forward to all comments. Dave KK4WW Computer Collector/Historian.
Thanks for the look inside! To clarify on the power capability, I see in the Matchbox documentation that that 275 W is -- just as we rated ham transmitter power in those days -- _input_ power, not output. Assuming 70% efficiency -- pretty optimistic :-) -- that equates to 193 W output. So saying that it's a "200-W" tuner is fine, but 275 W _output_ would be beyond its ratings. On a hunch I checked the maximum input power of Johnson's mid-range transmitter of those days, the Viking Valiant. Sure enough, the Valiant was rated at 200 W input AM, 275 W input CW. So the (non-kilowatt) Matchbox was designed to handle the output power of the Valiant. Best regards, Dave/W9BRD
This is "AM" rated and the PEP equivalent of 200 watts is 800 watts PEP (in AM Mode). especially in digital modes or SSB, it's good for more than 500 watts continuous (non-AM) operation.
Awesome old tuner. I got mine with a johnson viking ll and a hallicrafters sx 71 rxer. My tuner is different as it has a meter and two knobs up at the top. I also got an external vfo with the viking. ;-) all for 100.00
Eric 12374 Yes Johnson made some of the best radio equipment in its day. Thank you for the comment Dave www.kk4ww.com
Eric 12374 Sound like you have a nice old ham radio system. I also have SX71 but no Viking 2 - I do have the old ThunderBolt amp and driver. Don't think I will ever put them in service. dave www.n4usa.com
We are located in Floyd Virginia - the heart of the Blue Ridge Mountains and 6 miles West of the Blue Ridge Mountains. The LCF Group has available for the public a community amateur radio station N4USA and a Historical Microcomputer Museum. We welcome you to come by for a visit. The LCF Group also keeps lots festivals & events going at our Chantilly Farm We have annual Bluegrass festival ever in May on Memorial Day . A beautiful special event hamradio station N4USA at farm also -Dave KK4WW
hi,sorry my english.
can you tell me if i match box is good,or is not neccessary?
thanks men.
Paulobraveheart ios Hi - It depends on the antenna if a match box would be needed. The Match Box is a very old tuner you would want a more modern tuner like an MFJ product or similar. Dave
Hi Thank you all for viewing my videos
I do a computer blog -- TAKE A LOOK microcomputermuseum-com
Thank You Dave KK4WW Computer Collector/Historian
Sorry but the original design is a POS