Anybody on 3885 tonight?

[AF9J]

The VFO came with a homebrew power supply (it's actually bolted to it).  So, short of doing one more monkey move in my transmitting scheme (switching the VFO to standby, when I'm not transmitting), I'll have to come up with a keying line.

Ellen - AF9J

[W1GFH]

Glen E. Zook, K9STH, sells the VFO plug assembly for the crystal socket. You could also fashion one from an old busted FT243 crystal. Many people just solder a couple of old tube pins to a pigtail lead and apply heatshrink.

The Heath AT-1 xmtr supplied power and keying to the VF-1. I wonder if the Globe 680 has any such conveniences on the rear panel put there to control Globe's V-10 VFO?

[AF9J]

It might.  I've been thinking if ditching the old power supply, so I can just leave the VFO on, and key the VFO through the power feed.  I'm beat.  I got home late from the animal shelter I help out at after work on Mondays.  My ankle I twisted badly a week and a half ago aches, and I'm only now starting to eat supper.  I think I'll screw around with this tomorrow, when I have more time, and errors from exhaustion are less likely.  I already have the VFO plugged into the crystal socket. It's now just a matter of keying it.

73 & Good Night,
Ellen - AF9J

[WQ9E]

Hi Ellen,

For testing purposes just leave the VF-1 in the on position and you won't have to key it at all since ON grounds the cathode keying line.  Otherwise all you have to do is hook up the high side of the VF-1 keying line to the high side of the keying jack in your Scout to key them both.  To power the VF-1 from the Scout you will need to provide an additional dropping resistor for the B+ since the Heath rigs intended for use with the VF-1 have an internal resistor for this purpose and produce around 250 volts under load at the B+ output (instead of the Scout's 500 volts); you can add an additional 18K 10 watt resistor in series with the B+ feed to connector 3 to the Scout's accessory socket.  I imagine that there is plenty of room under the Scout's chassis for this addition but don't mount it too close to a filter cap or anything that doesn't like heat.  Otherwise, for powering the VF-1 from the Scout connect Pin 1 from VF-1 to Pin 1 of Scout accessory connector (ground); Pin 4 of VF-1 to Pin 3 of Scout (B+); and Pin 2 of VF-1 to Pin 7 of Scout (6.3 V filament).  It looks like from my schematic that Pin 8 of the Scout accessory plug is not used so if this is the case you can connect the cathode keying line in the Scout to the unused position 8 and connect this to Pin 8 of the VF-1 for keying.

I hope this makes sense, I have been up since 2:00 A.M. working on a journal manuscript and this is quite a switch from a critical look at green marketing to high tech, 50's style!

73, Rodger WQ9E

[KA1ZGC]

I'm probably overlooking/misreading something (I'm tired), but if the VFO were keyed by keying the power feed, wouldn't that make spotting a bit of a challenge?

Ellen - too bad you crapped out early last night. Conditions went VERY long a little after approximately 22:00 EDT (IIRC). I was in a roundtable with Steve KC2JXX and Bill KC2IFR when they both went from solid strap to barely even perceptible in a span of about 5 minutes.

It was like suddenly finding yourself on 20 meters, out of nowhere, for no appearent reason; a paradigm shift without a clutch.

Fortunately, Bud WD8BIL jumped in at that moment and was heard by all three of us. He was able to pass along that none of us were hearing each other, only him.

TNX AGN, Buddly, for the use of WD8BIL/R! 

Anyway, that's been the nature of the beast for a few weeks now and will likely continue right through the winter. The sun is in Clearasil mode and probably won't have many signifigant acne outbreaks, so the MUF should stay nice and low, making for good long-haul conditions on 75; minus any auroral activity we're due to start getting any day now.

Good luck with the rig(s), and we'll keep the band warm for ya!

--Thom
Keep Away One Zorched Germanium Capacitor

[WQ9E]

Hi Thom,

The power feed is not being keyed, just the connection that grounds the cathode of the 6AU6.  Given that the Scout uses direct cathode keying a lot of solid state keyers probably won't be happy with the open circuit voltage level however!  This type of keying is also more likely to cause chirp on CW, particularly on the higher bands due to multiplication of the VFO signal but it really isn't an issue on AM.  The "time sequence" keying used in many of the Johnson rigs does a pretty nice job of allowing break-in without chirp issues.

73, Rodger WQ9E

[AF9J]

OK everybody I'm screwed up.  Is the keying for CW, or do I also need trhe keying for AM?  I assumed that I need the keying for AM too. 

Thom, it figures that on the one night I'm trashed from a lack of sleep, and getting home late, the band would be in killer shape. <sigh!>  A yes, you mentioned Aurora, bad for low band stuff, but cool for 6m & up CW.  AU is fun!

73,
Ellen - AF9J

P.S. - using a keyer with the VF-1 & Scout is no big deal to me.  If I use 'em for speed CW, I'll use my Champion Bug.

[AF9J]

OK, I tried out the VF-1 a short time ago.  I got plenty of grid drive during tuneup (I had to back off the drive to 2 mA).  And I was able to tune the final.  Modulation audio on AM was good.  But I have a problem.  My output and carrier are low.  ON CW, I'[m only getting 10W out.  On AM, I'm getting maybe 8W of carrier.  That seems kind of low. I'm not sure if the VFO tube is weak, or if it's something else.  You see, recently I learned I shouldn't run the 6U8 Driver's grid current much more than 2 mA (2.5 mA max).  The manual says use 3 mA.  So, I've been working it hard.  Also, I found out that 6146s do not take kindly to being run above 110mA of Plate Current.  The manual says to use 125-130mA of Plate Current.  By normal (dip the plate current & peak the load) procedures, I wasn't getting the manual specified values, so more than likely I've been mistuning the final.  When I follow normal tuning procedures, I get about 100-110 mA of plate current.  I'll have to check things out some more.  I may have to dig out one of the spare Chinese 6146Ws I have, and replace the final tube.

73,
Ellen - AF9J

[AF9J]

Ahhhh, nevermind the last message post.  I rechecked the tuning procedure in the manual.  It's goofy compared to the procedure my TS-820 uses, or the Drake T4XC I used to have, used.

After the first dip in Plate Current, you're supposed to only load up to the maximum  Plate current (in the case of a 6146 - 110 mA), then redip, reload (again to max  plate current), and repreat until things settle down.  I did that, and it's fine.  I got 20 plus watts of carrier, which is about on a par with a Johnson Ranger.  My modulation was also good.  It's ready to go.  All I need to do, is work on the dial movement (it sticks at a couple of points), and receiver muting switching.  As it is, I can run it right now if I need to.  BTW, I didn't hear the VFO in my receiver,when I left it running after I quit transmitting.  Am I going to have issues if I leave it running, when the Scout isn't on transmit? 
 
73,
Ellen - AF9J

[KA1ZGC]

That's pretty much the procedure for tuning any tube final: peak the grid to the appropriate drive level, seek out your plate dip, load for appropriate current, re-dip, re-load, ad nauseum until you find the tube's Happy Place. Periodically re-check the grid as you go, if things were way out of whack when you started then the two will influence each other, but get better isolated when you get closer to optimal tuning.

Don't know what your rig runs for voltages on the 6146, but it sounds like similar levels to the Ranger. It should be perfectly happy at 110 mA, and may not blush too much at 120-125 mA if everything else is lined up correctly. You may start running out of headroom, though, so best to leave things where they are until you start getting the feel for the rig's mood swings.

FWIW, the 6146 in my Ranger likes life the best with the grid at around 2.5 mA and 120 mA on the plate. That's a Ranger, of course, and the voltages are probably different, not to mention other differences in the input and output circuitry. YMMV.

You didn't hear the VFO when you unkeyed, but did you have the BFO on? If you were listening in AM it may well be that the carrier was weak enough to get tromped on by and static and noise you were hearing, so you just didn't notice it.

I know when I operate from Tim's that his Ranger II barely has any spot level in low power, and more than once I've gone to high power to find myself and forgot to switch back. It's a good thing I habitually turn and check the meters on the 610 when I transmit, otherwise I probably would have cooked his 4-400 several times over! It's only a matter of time before I do the exact same thing to this 4-250 of mine.

That being niether here nor there, it sounds like you've got it pretty well dialed in, and you're just a relay away from a full-blown AM station, just in time for the low-static season!

We'll keep an ear out for you in the evenings. Good luck!

--Thom
Kilimanjaro Africa One Zulu Goat Cheese

[AF9J]

Thanks Thom,

I hope to get on tonight after work.  If I can get on before it gets busy, I may try 7290 (if it isn't too late).  Otherwise, I'll try 3880 (I think the weekly Collins net gathering is tonight), 3885, 3710, or 3725 (if that stupid all sports format AM station nearby, isn't breaking through the SX-96).

73,
Ellen - AF9J

[ka2zni]

Hope to hear some activity tonight as well.. Will be home until about 9:00Pm.. Worked a few stations this morning and this afternoon... The Yaesu FT 101EE/Dentron Clipperton are working VERY well together... 


'73's All,
Kevin - KA2ZNI

[W1GFH]

BTW, I didn't hear the VFO in my receiver,when I left it running after I quit transmitting. 

Hmm. You should be able to hear the VFO in your rcvr when using the BFO. Otherwise, the "spotting" feature will be useless.

[AF9J]

I had to deal with some things, so my time hasn't been free until now.  I just checked 75.  A fair amount of SSB, but I'm only hearing weak carriers for AM.  I'm debating firing up down around 3710.  I took a listen on my TS-820, on 160m.  There's a nice AM roundtable happening on 1978.  <sigh!> Of course, I DON'T have 160m AM capability.

73,
Ellen - AF9J

[WA1GFZ]

I was on 3885 with Todd's KWM380 a while ago sorry if I trashed anyone gfz

[AF9J]

Nah, you're fine Frank,

I'm just not hearing much on 75 tonight AM-wise. 160 sounds better for AM.

73,
Ellen - AF9J

[KA1ZGC]

3880 went long by about 2200 EDT. I was hearing lots of southeast traffic and a few guys in the Bayou, but nothing very strong.

Funny you should mention 3710, I tuned down there after 3880 crapped out and heard K4KYV in QSO with a few others, all very strong, so I killed the filaments on the Junkyard Dawg, tuned the Ranger up in low power, and walked out to the doghouse to retune the antenna...

...only to find my SWR meter is totally dead. No way to re-resonate the antenna now. Looks like I'm stuck in the 3885 neighborhood until I fix the meter or get a new one.

Probably my fault, I left the meter in the 200W range and never thought to flip it up to 1kW when I installed the Junkyard Dawg. I probably cooked it. I'm going to autopsy it this afternoon. Maybe I can at least get it to deflect in the 1kW range.

Remember, boys and girls, ham radio can be FUN!!

Maybe catch you in the 3885 region some evening.

--Thom
Keep Away One Zorched Gain Comparator

[w5omr]

Funny you should mention 3710, I tuned down there after 3880 crapped out and heard K4KYV in QSO with a few others, all very strong, so I killed the filaments on the Junkyard Dawg, tuned the Ranger up in low power, and walked out to the doghouse to retune the antenna...

I'll fire up on 3.710kc this evening around 2200CDT (11pm for youse guys) and see what can be heard. 

I worked Dave/W9AD in Barrington Hills, IL this morning, and he was full quieting down here in South Texas.  Got a 20 dog-biscuits over S-9 report from him, and I was running 100w of carrier output.

...only to find my SWR meter is totally dead.

I fried the metering circuit on my Heathkit SA-2060 'tuner by carefully, slowly and methodically moving the transmitting apparatus down to 3.650Mc, back on the 14th of December for the Band Warming Party, when we got the 'new' voice frequencies. 

Got off the air around 2am, and for whatever reason, was up early enough to get on in the morning.  Quickly swung the VFO back up to 3.880, and without thinking, flipped the plate switch on the Viking II (which drives the push-pull 250TH rig that -was- running 300w, 230kc's south on the band...

*ZOooooorrrRRrrrrccccchhhhhhh!!!*

@#$%^!  Where's my #$%^'in' Coffee?!?
~sigh~

Now, I'm using the same tuner, with the metering circuit cut loose and an external Heathkit Power/Swr meter with a -real short- (6") RG-8 jumper to go between the final and the tuner, which feeds 450-ohm ladder line. 

I've not seen any balanced line wattmeters 

[KA1ZGC]

Yeah, it can be a genuine pain in the ass what that happens.

This is (was) one of those Kenmore SW-2000 "remote" multitesters. It sat out in the doghouse in line with the link-coupled tuner. I used it to resonate the antenna when I change bands or move more than 30 kc or so. I had been using it in the 200 fwd / 100 reflected mode since I had mostly been running the Ranger.

When I lashed the Junkyard Dawg into position, it never dawned on me to walk out to the doghouse and flip the meter to the 1kW position. Too late now. Meter, she go "zorch".

Unfortunately, that's the last of my VSWR meters at this place, which means I'm stuck in the 3885 neighborhood until I get another one. Radio Shack wants $50 for theirs, which I can't justify right now.

I'll listen around for you guys, but my transmitter is stuck in the 3885 neighborhood until further notice. 

--Thom
Killer Agony One Zipper Got Caught

[AF9J]

Hmmmmm,

Work's been kind of nuts here today, so I haven't been able to reply until now.  So the band went long - that makes sense to me.  It sounded a lot like 40, when it goes long.  Like I said earlier - I heard a great roundtable going on around 1978 Kc.  Great signals.  Some were well over S9 (even those, west of the Mississippi).  It sounds like I'll have to get on earlier tonight.  I wish I had 160m AM capability.
Anybody know of any cheap, simple transmitters to make for that band (or cheap single band, 160m  transmitters?). 

Geoff - I d on't know if a balanced feed wattmeter was ever made (if so, they're very rare).  I have a feeling that the RF wattmeter is mainly a WW2 era development (which explains why even wattmeters from the 50s use SO-239 connectors).  Before WW2, it seems that power was mainly done as input power (through calculating plate voltage x plate current).  As for antenna purposes - from what I've read, prewar Amateurs (and I think other radio services) mainly used an RF ammeter inline with the  antenna feed, and tuned for maximum antenna current.  In many cases their SWR was sky high, but as long as the finals were doing OK, it was no big deal to them.  They didn't really care about SWR.

73,
Ellen - AF9J

[w5omr]

  As for antenna purposes - from what I've read, prewar Amateurs (and I think other radio services) mainly used an RF ammeter inline with the  antenna feed, and tuned for maximum antenna current.  In many cases their SWR was sky high, but as long as the finals were doing OK, it was no big deal to them.  They didn't really care about SWR.

And, to tell you the truth, tube transmitters -still- don't care about high standing wave ratio. 

Besides, to read -true- SWR of the 'load', the meter measuring point should be at the feed point. 
There's going to be some SWR on the feed line (whoop-dee) but all the line is doing is transferring the Z of the load to the Z of the final.

For that matter, I'm thinking about just doing away with the tuner, modifying my 'real-life, honest to goodness Faraday Shielded Link' back to having dual outputs, and just tying on the 450 ohm ladder line to the link output.  Adjust the link for a fair load on the push-pull 250TH's, listen to it in the receiver for audio quality, monitor the plate current meter, the plate voltage meter, guesstimate 75% efficiency and rock-on at around 250w, max. 
(My symmetry ratio is 3, sometimes 4, on the scope)