Tag " home made"

My kids are learning Morse code this summer, so I threw together this little circuit to help them learn. And to make it more fun... It uses an ATtiny85 ($2.26 at digikey.com) to drive a piezo beeper (? $3.50 at Radio Shack.) The ATtiny85 takes 5.5V max, so I built the circuit on a piece of strip-board so as to fit onto the back of a 3-AA-cell ($3 or so at Radio Shack) battery pack. To program...


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Big boys - Big Power. The 3CX15000A7 amplifier 3-23 MHz. 25 kW SSB output. Photo: w8ji LINK


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Seems that problem solved with second CAT for "FT857d" YAESU. I've build a new CAT Interface for MixW and WIN-TEST (WT) applications. Everything working OK


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The MAKRS80 is a QRP transceiver designed for use for use on the 80M band, the circuit was developed from the BITX20 designed by Ashhar Farhan. Although simple in design perceived performance is as good as a commercial transceiver. Main changes from Ashhar's original design are the inclusion of a frequency counter and a Huff and Puff frequency stabiliser; this circuit will help keep the VFO tuned...


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by NE7X ... To resolve this QSK problem I decided to replace the slower mechanical T/R relay in the Henry 2K-4 with high speed Gigavac model GH1-HAM (datasheet) 5KW RF 6ms 12VDC SPDT vacuum relays. Not only will this resolve the issue of having the IC-7700 transmitting into an open circuit every time I key the transmitter, it will also allow the amplifier to run full QSK break-in. I found...


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# PCB size 75 x 49 mm up to our analog sequencer boards. # The entire control needs to be done by a small PIC 12F629/675, to save space on the board (the 12F series has only 8 pins, but that only 6 possible I / O ports for input and output). # A memory is sufficient, but the speech must be switched into a loop. # Recording and playback of the message should be signaled by an LED. # he AF output...


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Source: QRZ.ru Forum


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WD6CMU wrote: Field Day 2003 was the testing ground for the third generation tennis ball launcher, dubbed "Trident". Two legs and the apex of a 400' vee beam were hoisted with three shots, a fourth shot was used to pull a messenger line over the beam to pull it loose from tree snags -- a 100% performance record on its first try out. The 5lb Trident also proved to be handy in the field, easily packed...


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