Thanks for all of the help.  W2AEW's youtube videos helped.  I wonder if there will ever be a solid state version of YouTube.  Hi Hi.

After pouring over my books and the circuit diagram for the TT 525D Argosy, I've come to the following conclusions.  This particular rig indicates the LO frequency on the digital readout at all times.  In CW receive mode, a 9Mhz IF is beat against a 9MHz BFO.  So in order to hear a CW signal, one must tune the VFO to get a 750Hz audio tone.  On transmit, the BFO adjust to 9000750 Hz to combine with the same LO frequency.  The end result is that both transmitters transmit on the same frequency.  I think this is a bit unorthodox, but interesting nonetheless.  What is particularly curious is that the digital readout of frequency is 750Hz inaccurate on transmit (in CW and SSB reverse only).  The TT manual specifically states the same.

I confirmed these theories by listening to K2SDR's WebSDR in NJ.  I was able to compare his waterfall sigs with the same signals I'm receiving here in NYC.

This has deepened my knowledge of transceiver design. 

73,
Charlie

I am obsessing about my Ten Tec Argosy II and wondering how the magic works when it receives CW.  It is operating perfectly, I am just an amateur trying to understand how the parts work.  Here are the facts for the receiver part of the rig:  superhet, IF of 9.0Mhz, fixed sidetone of 750Hz, CW mode BFO is 9.000750 Mhz.  The PTO/LO feeds a frequency of 5.0 to 5.5 Mhz to the receive mixer to yield the 9 Mhz IF.  I operate almost exclusively CW on 20m.

Like all of you, I've observed that a CW signal at, say, 14.060 Mhz will go from higher pitch to lower pitch as I tune from below 14.06 to above 14.06.  During such tuning, the PTO/LO signal is going from (for sake of argument) from 5.058 Mhz to 5.062 Mhz.  The receive mixer then results in an IF of 9Mhz.  This 9Mhz combines in product detector with BFO frequency of 9.000750 Mhz thereby yielding the pleasant tone of 750 Hz.  I understand.  What is confusing me is this:  this process does not explain the changing tone as tune through the transmitted signal.  Can anyone help me understand?  I'm hung up on the fact that regardless of where you tune, you will have a 9Mhz IF which results in 750 Hz tone no matter your relation to transmitted CW signal. 

I hope this question is clear!  Thanks for help.  I'm trying to deepen my knowledge of receiver design. 

72,
Charlie

I was originally licensed in April of 2001 as KC8RFV.  Shortly before 9/11/01, I moved to new york city.  I couldn't resist a vanity call (I was heavily into CW at the time).  My vanity call is now N2YF since about 2004 or so.

I'm wondering who had this call prior to me?  Does anyone have old call books or knowledge of such a thing.

Many thanks,

Charlie
N2YF

I've been operating a FT897 (late model) since 12/03.  It's versatile, seems durable (aluminum frame and case)and has internal batteries for portable ops which I'm into.  The 897 does what it's designed to do; it's sort of a niche radio.  From Manhattan (with a glut of RF, concrete and metal) with a dipole up 40 feet and 100 watts, I've worked plenty of US states and even some European and South African DX on 20 meters.  With the stock mic it gets good, unsolicited audio reports with the right gain/processor settings.  I work primarily SSB.  Check out the Eham reviews and the yahoo groups at http://groups.yahoo.com.  I would love an Orion or some other Cadillac rig if I had the space and a giant tower in the middle of nowhere, but for my space situation and need for portability, this thing can't be beat.  And since I don't drive in New York City, I don't need a mobile rig the size of a sandwich.  It's all about what fits your needs.  Try building the PAC12 portable, vertical, breakdown antenna (do a google search for build plans).  It's super inefficient, but fun and versatile.  Just some ideas...Have fun and 73


Charlie
N2YF
formerly KC8RFV

I'm traveling to Puerto Rico next week, and I plan on taking my FT 897 with a trusty tuner,wire and batteries.  Will my US license suffice in PR?  How should I identify my station?  

Also, I'm a little nervous packing my radio as carry-on baggage at LaGuardia airport what with heightened security and all that.  Any advice or experience would be helpful.  

TNX
Charlie
KC8RFV

I'm homebrewing the PAC12 HF vertical antenna which calls for loading coils of 22 gauge wire wrapped around 0.5" diameter PVC pipe (various lenths and wraps depending on band).  The problem is this: I haven't been able to find 0.5" PVC, just 0.75" diameter PVC.  If the antenna design calls for 23 wraps on 0.5" PVC (22gauge wire) for the 20 m band, how many wraps (same wire) are necessary on 0.75" PVC (same band)?  I don't have my reference books (they're in storage), and I assume there is a mathematical equation to calculate capacitance, etc.  What is it?  I was also wondering this: can I measure the inductance of a coil with a multimeter?  I know this is a lot, so thanks in advance.

I know I should know the answer to this, but it's been awhile and my books are packed away.  Due to space restrictions at my home QTH (Manhattan), I am setting up my rig at my parents' place in Pennsylvania for weekend operation.  What is the accepted (and possibly mandated) method for station identification?  Thanks!

This may sound like a nit picky question, but it will help me test the regenerative receiver I built.  It utilizes a couple of 50-150 pF air dielectric variable capacitors.  The capacitance as measured by a DMM checked out fine prior to installation.  However, now that the capacitors are coupled with the wound toroids and ground, the measured capacitance is out of range or immeasurable.  Is there something wrong with the circuit?  Or does measured capacitance change once a capacitor is coupled to a coil?  I'm just trying to get my regen to work - I think the real problem lies within my audio output and impedance matching with headphones.  This measured capacitance problem would help, though.  Thanks a lot.

I think old "Bart" here is yankin our chain.  Maybe "Bart" should query himself as to why a bored, 40 year old man would get his kicks off of tormenting the amateur radio community with child like pranks.  Know thyself, Bart, before you start examining others.

My noise blanker was NOT on, it was definitely CW - I just can't remember the call.  Well, I guess it wasn't a spark gap- silly me.  I thought they might still be used.  Thanks for the input.

Over the last month I've heard a CW station sending a raspy, hissy tone that was a strong, constant RST 59? on various occasions.  Is this a spark gap generator or auroral flutter?  I would guess its a spark gap, but I wasn't able to work the fellow to find out.  It was on the CW portion of the 20 meter band.  Just curious.  By the way, if it is a spark gap generator, how do you build one as a transmitter?  

Just built a soundcard interface for my Ten Tec Argosy.  I can receive and transmit ok - the problem is that my transmit frequency is ~100 hz down from my receive frequency such that I can't stay "locked on" to another station during a QSO.  I suspect VFO stability changing on transmit.  I probably am only now noticing it since I am using a mode with bandwidth of 30 Hz.  Can I do anything to fix it?  Are there other possibilities for the problem?  What do you all think - you never steer me wrong.

I made an outdoor dipole with a SO239 connected to the center insulator.  My RG8 coax (bury flex) is connected to it via a PL259.  I mounted the PL259 myself and I did it well.  I used coax tape to seal around the base of the PL259 connector where it threads onto coax outer jacket.  However, I do not know if entire assembly is water tight.  I know water will ruin coax.  Any recommendations on making this as water tight as possible so I don't have to buy new coax in 6 months?

I've figured it out with your help.  I was measuring impedance with 50 ft of RG8 - hence the confounding picture.  Thanks so much.  Now I know how to properly use the impedance measurement.

I'm perseverating on antenna building of late, and I have yet another question.  I've built a 10 m dipole that works perfectly.  The SWR is minimal at 1.3 around 28.000 to 28.250 MHz as verified by my transceiver meter and an antenna analyzer.  The impedance is maximal at 68 ohms at 28000 MHz, and goes to a minimum of 20 ohms at 26.700 MHz, however the SWR is ~3 at 26.7000.  So, my question is this:  where is it resonant - at the SWR minimum or the impedance minimum?  According to my reading, impedance dip is the best measure of antenna resonance.  i know that there is no reason to alter my 10 m dipole.  But for future antenna building, should I use the minimal impedance point as an indicator of resonance or the minimal SWR?  If minimal SWR and minimal impedance indicate resonant frequency, why don't they correspond.