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Author Topic: lucky contact with old one tube mopa  (Read 1552 times)

Offline ve3lyx

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lucky contact with old one tube mopa
« on: July 08, 2016, 10:56:03 UTC »
Yesterday I was working on a dualtriode mopa I built a year or so ago. I had used a 6bl7 originally and was never happy with it. It is a slug tuned fixed cap in the osc and a parallel tuned tank in the PA side ad a single tube dual triode. I tried a 6080 but the power supply stated to over heat from the big tube. I had a euro equivalent for a 6sn7 but it didn't like it (this maybe a bum tube because nothing I have likes it). Then I switched the Power supply for 12 volts fil and tried a 12sn7. Sounded pretty good so I hooked up the antenna and clipped on a ground. Yesterday conditions were dead. Prop reports stated POOR both night and day. I tuned up on 7044 as I have been hanging around there for another reason anyway listening for a friends rig. I called CQ and heard someone key down. I called again and heard him tuning. very faint but with no one else on readable most of the time. I heard him again and sent a ? and a K with my call. Then I heard my call coming back to me from WA1JAS. Sig reports were 229 and 239 so you get the idea I am sure but we were able to pull it off because the band was clear. I know I don't have much power out but it must be enough. Sure was fun. QRP with tubes!
don VE3LYX

Offline GM0LVI

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Re: lucky contact with old one tube mopa
« Reply #1 on: July 14, 2016, 23:13:30 UTC »
That's the magic of QRP radio Don and the magic is doubled with home-brew gear!
QRO doesn't have a look in when it comes to kicks.
Dave