Barry, You'd be amazed how much nicer the Corsair feels with the original tuning knob driving an encoder rather than the PTO. I even epoxied some steel nuts to the inside of the knob to give it extra
Barry, The tuning rate of Joe's DDS is velocity dependent - if you spin the dial fast it quickly goes from one end of the band to the other. At its slowest rate it is close to 1kHz for one complete t
Perry, I haven't tried it. If I get a chance over the next couple of days I'll do some tests. It would be nice to get some thorough testing done of Rx performance when equipped with the DDS, but I do
Greg, The DDS modification still uses the Corsair's "native" frequency readout circuitry, so setting accuracy is no better or worse than with the PTO. 73, Steve G3TXQ Thanks! Greg, KC8HXO
Readout accuracy is entirely dependent on the Corsair's "native" counter board; VFO frequency stability is entirely dependent on the DDS reference oscillator. What the DDS does *not* have is the 10kH
Perry, I took a quick look this morning. I keyed the Corsair at 30wpm, fast QSK, and 100W output into a dummy load. I tried 50kHz and 200kHz frequency splits. I listened to the signal on a monitor re
Chris, Is the receiver silent in ALL positions of the filter switch? 73, Steve G3TXQ On 26/03/2011 22:21, tubsc66@aol.com wrote: Hi everyone, I've added a Corsair to my TT arsenal, its an original gr
Paul, When you say "bandwidth" I presume you mean "VSWR bandwidth". The Resistive component of the feedpoint impedance of a dipole varies relatively slowly with frequency either side of resonance, bu
I need to replace a fault "Notch" potentiometer on my CorsairII. It's dual-gang, and mounts to the IF/AF PCB as well as to the front panel. I can't see anywhere on the schematic that tells me its Ohm
Neil, For some reason I'm not receiving list postings via my email - only just found your response on the web archive for the list. This is a "spare" Corsair I bought very cheaply a year or so ago. I
The potentiometer wasn't marked other than with a manufacturer's number. It measured 211k across the ends, and mid-way on the rotor the resistance from the slider to either side was 176k/35k, so I th
Jerry, Thankfully, none of that is necessary. It's a stock item: http://www.maplin.co.uk/standard-dual-gang-potentiometers-2207 Steve G3TXQ On 07/02/2011 16:15, Dr. Gerald N. Johnson wrote: Dual, sin
Jerry, I don't know why it would be different here in the UK, but 220k seems to be a much more common value than 250k. Here's a typical distributor: http://www.electronelec.co.uk/acatalog/Electron_El
Jerry, Now you mention it ......... My recollection of the sequence of events was that the Notch pot was a bit "scratchy" but operated over its full travel. Whilst I had everything apart for the DDS
Folks, The Maplin potentiometer arrived yesterday afternoon and I got a chance to fit it in the evening. It's not the "drop-in" replacement I hoped for, basically because it's slightly smaller than t
Jerry, Yes - it was disappointing. I can't think of any simple way of "fudging it". The Corsair filter circuit has them configured as variable resistors rather than potentiometers, so the usual trick
Charles, Thanks for the suggestions. I see a couple of problems: * The pot mounts directly to the PCB, so swapping the ends means cutting tracks which I'd prefer not to do at this stage. Of course if
Charles, I thought I gathered from your description that you actually ended up using wires to extend the pot leads. Or maybe I misread? I needed to extend by about 2mm, so I inserted short terminal p
I swapped the potentiometer this morning for the Maplin 220k linear version. It only took 20 minutes second time around, including shortening the new spindle and filing down the bushing. It "feels" s
Jerry, I did get a quote from Omeg. Their part with the closest match would have been 220k with a reverse log taper, the correct size spindle bush, a genuine 1/4" spindle (not 6mm) and the correct le