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Use of a small amp to boost the 5 W Paraset output
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N7RKC, Mike
Are there any rules governing the use of a 10W booster amp to compensate for the lack of a decent antenna with a Paraset. ??? Thanks //Michael T. - N7RKC
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All I use with my 5w rigs is an enfed. Cost is under $20 , easy to set up and use. Got France from Florida with one a few months ago and only need WY for WAS.
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Good luck with the BJ, just finished building mine yesterday, now need some power and run it through the paces. GL, see you on the air. John KK4ITX 🙃Each mistake is a learning opportunity.🙂
On May 1, 2021, at 5:12 PM, N7RKC, Mike via groups.io <emwizo@...> wrote:
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Curt
Mike
Each time we increase power 4X the impact is roughly 1 S unit at the receive end. So going up to 10w is a pretty small change. Also, to drive a typical 10w RF amp you will likely need to modify the paraset to output less than 1w. A lot of effort for little gain. If antenna space is scarce, evaluate if you erect something at least partly vertical. A UK ham has a small garden vertical antenna on line that looks rather nice. Curt wb8yyy
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griffithsesq.robert
Roger that. One of my first QSOs with my first Green Panel Bayou Jumper was with a station in Normandy, France, commemorating D-Day, the 6th of June. That daylight QSO was on 7.030 MHz using a bent and shortened 80/40 Dipole in my attic. The antenna is more important than adding an additional 5 or more Watts. However, do use a tuner in between the BJ and the antenna if the antenna is not resonant. Try it and have fun. 73. Griff NE3I
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Robert Alan Griffiths
On May 1, 2021, at 7:44 PM, John - KK4ITX via groups.io <jleahy00@...> wrote:
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Tom Sevart
On 5/1/2021 14:23, N7RKC, Mike via groups.io wrote:
Are there any rules governing the use of a 10W booster amp to compensate for the lack of a decent antenna with a Paraset. ???Yes, you can only use one on days that end in Y. -- Tom Sevart N2UHC St. Paul, KS -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Darryl K4VLP
I’ve checked with Bletchley Park. As long as it fits inside your suitcase and doesn’t tip off the Gestapo, it’s bloody good show.
Darryl K4VLP
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griffithsesq.robert
John, KK4ITX, do you direct feed the the end fed or use a tuner in between it and the BJ? What is its length? Does it incorporate any Balun or Unun on the Transceiver end. Do you use any counterpoise with it? Thanks. Griff NE3I
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Robert Alan Griffiths
On May 1, 2021, at 7:44 PM, John - KK4ITX via groups.io <jleahy00@...> wrote:
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Hi Robert,
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I have several antennas that I use while operating portable with my FT-818 or other rigs. Lately I have been using a QRP Guys EF see attached pic, this is the one I will use on the BJ, no tuner will be required. Once the wire has been cut to tune for 7040 I will then fold the wire back on itself and mark the match spot for around 7115. That should put me in the center of the two working areas. I have built several 9:1 UnUn’s and use one at my QTH but it needs a tuner. I have just finished the BJ, tested it and all seems OK. Having 1000’s of feet of wire it’s odd that I don’t have a foot of 18-20 ga red & black wire for the power plug and can’t find any locally ! Hope to catch you on the air soon, John KK4ITX
On May 4, 2021, at 06:58, griffithsesq.robert via groups.io <signalnaut@...> wrote:
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Bob Parr
I use about 66 feet and get it up in the trees in an inverted L or sloper form and a 30 counterpoise on the ground going in the same direction. I use the 4 States Tuner and it seems to work well.
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Bob KG5GTE
------ Original Message ------
From: "griffithsesq.robert via groups.io" <signalnaut@...> To: main@4sqrp.groups.io Sent: 5/4/2021 5:58:21 AM Subject: Re: [4SQRP] Use of a small amp to boost the 5 W Paraset output John, KK4ITX, do you direct feed the the end fed or use a tuner in between it and the BJ? What is its length? Does it incorporate any Balun or Unun on the Transceiver end. Do you use any counterpoise with it? Thanks. Griff NE3I
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N7RKC, Mike
It was just a question about getting a bit more signal out. Attached is my Blue panel set with self contained battery pack & home brew antenna tuner. Provides Coax & balanced output. After tuner loss it puts out 3.98W (Measured) into a trap Dipole hung into nearby trees. I am rethinking the tuner design for one with lower loss & possibly trying a ground wire counterpoise Haven't had a great deal of success with LD contacts so far. Thought a bit of extra power into the antenna could make the difference. KBO. Regards, Michael T.
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griffithsesq.robert
Thanks John and Bob for helpful Antenna information. 73. Griff NE3I
Robert Alan Griffiths
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I have been activating summits (now 144) with a QRP radio for the past three years and 5 watts (CW) have been plenty - albeit with dedicated chasers. The ones who need more power are SSB ops. I have been using end fed half waves almost exclusively. You can find some here - ny4gefhw.com. Footprint on 40m is between 200-800 miles with these antennas and a tuner is not needed and neither is a counterpoise needed.
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Ariel NY4G
On May 4, 2021, at 10:21, griffithsesq.robert via groups.io <signalnaut@...> wrote:
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Dale Putnam
Hi John,
I monitor the bands most all day, can be on at a good time for you?
Have a great day,
Dale - WC7S in Wy
"Actions speak louder than words"
From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of John - KK4ITX via groups.io <jleahy00@...>
Sent: Saturday, May 1, 2021 5:44 PM To: main@4sqrp.groups.io <main@4sqrp.groups.io> Subject: Re: [4SQRP] Use of a small amp to boost the 5 W Paraset output All I use with my 5w rigs is an enfed. Cost is under $20 , easy to set up and use. Got France from Florida with one a few months ago and only need WY for WAS.
Good luck with the BJ, just finished building mine yesterday, now need some power and run it through the paces.
GL, see you on the air.
John
KK4ITX
🙃Each mistake is a learning opportunity.🙂
On May 1, 2021, at 5:12 PM, N7RKC, Mike via groups.io <emwizo@...> wrote:
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If you use the 50 W CW KIT amp from Qrp Labs (about $30 USD) you will get 14 W true out on 40 M with a 14 V supply. that 's another 5.5 dB of signal at the far end. That amp will produce 45 W but only on a 22 VDC supply. It is specifically designed for QSK CW work though mods to make it a SSB amp are possible.
If you equip it with "bend pin " RD16HH mosfets you will get up to 20 W of clean CW rf out on 40 mtrs. THe efficiency will be about 55 percent. The RD16HHs can be got for about $12 a pair from Ebay Schenzen etc (if you go too cheap you will get fakes ) . Hans Summers ex Qrp labs does not sell those parts . THe RD16s are vastly better from a thermal point of view. NB you need to get an RX / TX 5V TTL signal out of the BJ to the power amp to control it the rx tx switching . that could be an issue - you may need to fit a TDO timer (CMOS 555) based on the CW key down so you will get only semi qsk in that case. The 50W CW amp is one off the deals of the century in terms of what you get for the money. The only ones that don't work are the ones where someone on cocaine wound the RF transformers or soldered the puppy up. If you do build one, consider fitting dpdt relays and a second filter set so you make it dual band. regards, TEF
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