The AM Forum
March 28, 2024, 06:30:17 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: 1 [2] 3   Go Down
  Print  
Author Topic: 630 meters  (Read 32330 times)
0 Members and 1 Guest are viewing this topic.
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #25 on: October 08, 2017, 06:08:22 PM »

http://www.472khz.org/pages/and-more/useful-links.php


Good info for you guys looking at getting on hmf (as a prior 172 kHz op....  Well..... ).

Antenna, amplifier, etc. Info all to be found their.

--Shane
KD6VXI
Logged
AJ1G
Contributing
Member
*
Offline Offline

Posts: 1283


« Reply #26 on: October 09, 2017, 09:07:16 AM »

The LST-325 probably has a TDE transmitter that will tune around the new freq. and being a good sized ship may have the decent aerial. I know there are hams involved with restoring the transmitters.
http://www.lstmemorial.org/

Perry Ballinger, W8AU, is one of the volunteer crew and is a radio operator on board during their underway operations.  He frequently checks into the Old Military Radio CW net during these operations using the ship's amateur call,WW2LST.  I think they have gone on the air on MF on some special operating occasions in the past, including the Armed Forces day crossband operations in May, using the ship's Navy callsign, NWVC, and their TDE transmitter.  The TDE covers both MF and HF, essentially two transmitters in one cabinet, 803 finals rated at 135 watts output on each frequency range.
Logged

Chris, AJ1G
Stonington, CT
N1BCG
Member

Offline Offline

Posts: 836


« Reply #27 on: October 09, 2017, 03:21:37 PM »

^^^ @KD6VXI  http://www.472khz.org/pages/and-more/useful-links.php

What a cornucopia of information, thanks!!
Logged
KB2WIG
Contributing
Member
*
Offline Offline

Posts: 4484



« Reply #28 on: October 09, 2017, 09:05:18 PM »


  "
             Kevin, I wonder if we'll be able to work each other.   "



I wonder.....

Maybe if I get the 160m eL up and running, and the wind blows the right way.....  I'd guess psk 31 would be worth a try - it's good for low sig levels. I hope to have the eL up before the Witch of November visits.


klc
Logged

What? Me worry?
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #29 on: October 10, 2017, 10:30:28 AM »

I'm thinking I'll try to be on with CW, PSK, and probably WSPR.

Tried to do some antenna work last night but got derailed and the sun went down. Did get on the anan again last night and I think the found the problem why I wasn't copying much with PowerSDR but could with cuSDR - the gain settings in PowerSDR were pretty low, lots of default attenuation in. when I took that out and got it to more normal levels, I could copy as well as with the RSP1 and cuSDR. The station in Stow was good copy again last night.

I then tuned around to see what else I could hear. I was able to hear a number of NDBs, nearly 20 logged. The furthest was in North Carolina! The closest was the middle marker at the local airport. So it seems I'm hearing reasonably well. I need to find my loopsticks or wind a coil to do some antenna matching as Clark suggested.

Did some more transmit tests into the dummy load. Looks like 10-20 watts will be possible. Current drain doesn't seem to be too high compared to higher bands.

Still scoping out the antenna options.

Anyone know where to find some of the part 5 guys who are currently on the air using different modes and their operating schedules?
Logged

73 de Kevin, WB2EMS
kb3ouk
Member

Offline Offline

Posts: 1640

The Voice of Fulton County


« Reply #30 on: October 10, 2017, 05:34:46 PM »

Last night must've been a good night down that low. Was hearing WD2XSH/31 pretty good, he's about 200 miles south of me. Was also hearing what could've been a couple of longwave carriers from Europe. Also had a carrier on 1215 khz which could've been from a station in England on that frequency.
Logged

Clarke's Second Law: The only way of discovering the limits of the possible is by venturing a little past them into the impossible
N1BCG
Member

Offline Offline

Posts: 836


« Reply #31 on: October 13, 2017, 11:33:20 AM »

I'm regularly hearing WG2XSB (471kc) and WD2XSH (478kc) at night. Anyone catch others?

Here's an interesting PDF article on 630M operation from Steve Johnston (WD8DAS):

http://www.wd8das.net/630mPractical.pdf
Logged
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #32 on: October 13, 2017, 03:03:27 PM »

Quote
I'm regularly hearing WG2XSB (471kc) and WD2XSH (478kc) at night. Anyone catch others?

I'm hearing WG2XSB on 471 most evenings, although sometimes there seems to be some QSB. I didn't know about 'XSH on 478. I'll listen tonight. Is he a CW beacon also? Are there other's you know about that we should try to listen for? frequencies and modes? Tuning around with the Anan I could see NDBs and the station on 471, but didn't see anything else in the 470-500 khz range on the panadapter.

Based on your screen shot of a 706, I dragged out my ICOM 703 and found it heard pretty well also. I hadn't remembered they were specified down to 30 Khz. Thanks for the reminder.

Looking for some caps to build a low pass filter to evaluate what's really coming out of the Anan and any other rigs I try.

Clark and Kevin, what kinds of transmit antennas are you thinking of? Right off maybe I could try the 40/60 meter dipole with the ends joined and working the 20 ft vertical section with the dipole legs as top hat. I guess you have to be careful of high voltage doing that, and that coax routes through the basement and out. Hmmmm.

Other antenna ideas include an inverted L as long as I can make it, an edington loop which looks like a 1/4 wave loop of wire, or a humongous magnetic loop made from a piece of heliax laying in the yard that I'd have to hang from a tree or two.  :-)

Who else is thinking of trying out this band? What are your plans?


When can people start getting on the air? I think I sent in my UTC thing the first day, and haven't heard anything back at least by email. Does that make use clear to go on the 15th or 16th if no contact?

Who's going to make the first AM contact on 630m and PO everyone? Clark, what are you modulating those 6146's with?  Shocked

 
Logged

73 de Kevin, WB2EMS
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #33 on: October 13, 2017, 04:19:07 PM »

Since I posted I've seen a small flurry of people posting on Zuckbook that they've received emails today from utc.org blessing their operation. So it looks like email notifications are starting to come out. I think I applied the first or second day when I saw a posting about it, so hopefully I'll see something this weekend. Might start to see some signals on there soon.
Logged

73 de Kevin, WB2EMS
KB2WIG
Contributing
Member
*
Offline Offline

Posts: 4484



« Reply #34 on: October 13, 2017, 06:43:03 PM »

I'm trying to put up a 160m eL....  for the last 6 or 7 years.  But I've got hope.

Murphy's Law radial design for inverted eLs...   1/10 wavelength...  works out to be 205 feet.  And 'they' like at least 16 radials. That looks like 6.55 rolls o Homleys despot thhn rolls. That and a garbage can for a coil form.


What I'll probably end up doing is loading up a 600 ohm resistor with the HP audio gen and see if I can hear it at the bottom of my driveway.


klc


FLASH!

I got my 'authorization' in email form this morning. So it looks like I'll be able to "get on" the new band.

Now if I can just do it in less than 10 years, I may be happy.
Logged

What? Me worry?
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #35 on: October 14, 2017, 03:25:06 PM »

Now I'm worried, mine hasn't come yet.😣
Logged

73 de Kevin, WB2EMS
KB2WIG
Contributing
Member
*
Offline Offline

Posts: 4484



« Reply #36 on: October 14, 2017, 05:04:06 PM »



Well, that's cause I'm special.


klc
Logged

What? Me worry?
N1BCG
Member

Offline Offline

Posts: 836


« Reply #37 on: October 14, 2017, 10:15:24 PM »

Here is one of the better web SDRs for checking out the 630M band. It's "pretuned" to 471kc for receiving WG2XSB * but you can adjust the frequency once the receiver has loaded:

Fair Hill, MD:  http://73.163.115.161:8073/?f=471.00cwz10

* Note that this station is not always operating but will most likely be heard in the evenings
Logged
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #38 on: October 16, 2017, 10:13:57 AM »

Quote
Well, that's cause I'm special.

Now I'm wondering whether I actually filled the form out completely and got it launched, or if I got distracted and didn't finish it. Not like that ever happens.  Shocked

Was scanning around last night to see if there were any new signals and BOOM, no3m popped up calling CQ. Easy copy, almost S9 at 473khz. I looked him up on QRZ and dropped a note with a reception report and asked what he was using as he was a really good signal up here. This is what I got back.

Quote
Kevin

Thanks for the nice report.

I have been QRV on 630M since about 2012 under the Part 5 calls WD2XHS/46 (ARRL Group) and WG2XJM.  I have a 67ft vertical and run about 100W or so into it now that we're 5 EIRP limited.  Rig is a K3 and VK3XK transverter with dual RX channels.  I usually run diversity RX with my 160M beverage arrays and a 630M 8-circle vertical array.  Some more details on my website if you're interested:

http://no3m.net/antennas/630m-antennas/
http://no3m.net/antennas/630m-8-circle/
http://no3m.net/shack/630m-station/

I may have mentioned FT8, a new digital mode that is becoming popular on HF now.

I had about 13 QSOs so far tonight on CW, JT9, FT8, and a couple on SSB.

Hope to work you on the band someday.

73 Eric NO3M

Take a look at the web pages - OMG.   He's working people on SSB!

I think I'll just quit now with my 20 watts and little wire antenna plans....

Logged

73 de Kevin, WB2EMS
ka1tdq
Member

Offline Offline

Posts: 1509


Red part turned in for a refund.


« Reply #39 on: October 16, 2017, 12:00:43 PM »

I have most of the parts to be able to slap together a Compactron tube and a DDS VFO for CW.  But, I'm in the same boat.  About 20 watts and a wire.  That guy has some serious stuff!

The pi network for the tube's output network has some crazy big numbers.  The only way to make the size of the components manageable is to use low power stuff.

My blessing certificate hasn't come in either.  I applied about 3 weeks ago.

Jon
Logged

It’s not just values, it’s business.
KB2WIG
Contributing
Member
*
Offline Offline

Posts: 4484



« Reply #40 on: October 16, 2017, 01:33:43 PM »


Watt you gata do is get some soft Cu pipe(3/4 in) and make something like a 3 foot diamater by 30 inch tall coil wound on a wood frame, slap a counter top on it and use it fer lawn furniture. At nite roll it to yer vertical and, like Curley, start broadcastinn.

Do it for the children.

KLC
Logged

What? Me worry?
N1BCG
Member

Offline Offline

Posts: 836


« Reply #41 on: October 16, 2017, 03:40:50 PM »

I got my 'authorization' in email form this morning. So it looks like I'll be able to "get on" the new band.

Wow!  I just received an approval email back from UTC.org.  Specifically, they said I was approved because:

UTC has determined that your proposed amateur radio station would not operate within a horizontal distance of one kilometer from a transmission line that conducts a power line carrier (PLC) signal in the 135.7 - 137.8 | 472.0 - 479.0 bands.

An amateur operator must not operate an amateur station if UTC responds that the proposed amateur station is located within 1 km of a transmission line with a PLC system that operates on the same frequency or frequency range.  Amateur operators are advised that their operations within 1 km of a PLC system could cause interference to PLC systems that are used by electric utilities to protect their electric transmission systems against faults and electrical outages.  Interference from amateur operations could affect the operation of PLC systems, thereby affecting the reliability of electric utility operations.  As such, amateur operators are advised not to operate any amateur stations within 1 km of a transmission line with a PLC system that operates on the same frequency or frequency range, and amateur operators will be subject to FCC enforcement for unauthorized operations, as well as potential legal liability for damages that result from interference caused by amateur operations to PLC systems.


So, this seems like a filtering system that checks the distance between the Lat/Lon applicants provide and the closest PLC system. If this truly is the last hurdle, then keep an ear out for the "All-New 475" coming soon...


* DSC03878.JPG (1567.44 KB, 2592x1944 - viewed 436 times.)

* DSC03879.JPG (1740.81 KB, 2592x1944 - viewed 359 times.)
Logged
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #42 on: October 17, 2017, 01:31:40 PM »

Sigh, still no joy from UTC here. I wish there was a way to check on the status and make sure I really did file it. I'm pretty sure I got all the way through, but if not, every day I sit wondering is one more day added onto the 30. Not that I have any kind of antenna yet.

Heard some more back from No3m.
Quote
There used to be a SSB net every Sunday night of the experimental operators on 510 kHz a few years ago.  Most where in the New England area, I was the outlier.  Most of the activity now is CW, JT9, and FT8.

That's interesting, I didn't realize that there had ever been any or much voice activity on the band. I thought it was all cw, QRSS cw, and digital modes like WSPR. I wonder if anyone has ever made an AM qso down low?

Ordered up a low power (5watt) LPF filter kit from over the pond. I'll need something with more power capability (I hope) at some point, but this will give me a start. Checked on the LP100A and they say it only works down low with the special coupler. Interestingly the power reading on the ME165 and the LP100a both agree on about 25 watts out on 630 meters. I'll have to parallel up a scope and see what the signal voltage is compared to the readings on the meters.  And I guess I'll probably want some sort of scope probe arrangement out at the variometer when we get closer to putting RF on the air.

No chance to listen last night. Did anyone else listen and hear any new activity?
Logged

73 de Kevin, WB2EMS
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #43 on: October 24, 2017, 10:16:30 AM »

Any new developments? I haven't heard from UTC yet, so just in case I refiled the form. That will give me more time to think about antennas.  Wink

Low pass filter hasn't shown up yet. Did get an upconverter kit for listening on rigs that can't go down there. Haven't had a chance to listen the last few nights - I imagine the activity must be starting to pick up.

Anybody else making any progress?

Logged

73 de Kevin, WB2EMS
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #44 on: October 29, 2017, 12:26:25 PM »

Found an interesting site today, a former marine radio op expressed his gratitude at mf and lf being granted to hams, and he relays some of his 'coastie' stories.....  Including copying a ship as it sunk, and the CW note changing in his ears as the radio room flooded.

Related to the discussion, thought I'd pass it along.  Cool reading, if nothing else.

https://w3atb.com/history-of-marine-radio-as-experienced-by-jeff-herman-kh6o/

Edited to actually include the link!


--Shane
KD6VXI
Logged
kb3ouk
Member

Offline Offline

Posts: 1640

The Voice of Fulton County


« Reply #45 on: October 29, 2017, 01:07:45 PM »

Found an interesting site today, a former marine radio op expressed his gratitude at mf and lf being granted to hams, and he relays some of his 'coastie' stories.....  Including copying a ship as it sunk, and the CW note changing in his ears as the radio room flooded.

Related to the discussion, thought I'd pass it along.  Cool reading, if nothing else.

--Shane
KD6VXI

Sounds almost like radiomarine.org since you didn't include a link, the website of the Maritime Radio Historical Society, which runs coast station KPH. Great website with lots of info and stories about what it was like back when MF was the state of the art for marine communication.
Logged

Clarke's Second Law: The only way of discovering the limits of the possible is by venturing a little past them into the impossible
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #46 on: January 02, 2020, 04:06:44 PM »

Resurrecting this old thread, I finally got back to this project, after a QTH move and sloooowly getting a shack back together in a temporary fashion while waiting for a shed to be delivered for a more permanent setup.

Over the holiday break, I built a 630 meter dipole with electric fence wire and insulators. I started up at 15 feet but after a few scary ladder experiences on uneven ground, I ended up doing most of it at about 8 feet, which isn't great, but the difference between 8 feet and 15 feet doesn't look to make a lot of difference. The proximity to ground greatly affected the tuning. I started out with roughly 985 feet, measured tree to tree with a rangefinder, and so far I've trimmed about 60 feet off each side and need to trim a little more. The good news is after the initial tuning at 406 khz, it's currently resonant around 459, and the tentec 238 tuner can get it to 1.3 swr at 474 khz measured on a the AA-1000 analyzer. I'll probably trim a bit more off tonight to sweeten it up some. If it turns out to be a total dud, I can always re-purpose it as a beverage antenna with some transformers and loads.  :-)

I let WSPR run last night and was copying stations from Texas and the left coast, so that wasn't too bad. Better than using the 160 meter doublet through a balun has been over the last few weeks.

Tonight I have to do a bit more checking out of the ANAN200D output on 630 - I want to measure the power output vs input current on 160 meter and 630 meters, to make sure it's not running too inefficiently, don't want to cook the rig. Maybe check the heat sink temp as well. If that looks ok, I'll use a scope to confirm the power output into a dummy load and see how far off the LP100 and various other meters are at those frequencies and take a look at the waveform, then set it for 5-10 watts and let fly on WSPR.

I talked with another ham down in Florida who is using a similar dipole and with his encouragement decided this was the easiest way to dip my toes into the world of 630 meters. As it happens, I'm blessed with enough room behind the house to run a pair of 500 foot legs so a 1000' dipole was actually the easiest thing to implement. Eventually I'll maybe try a T antenna or other options if the band proves interesting.

Wondering how other's foray's into this band went. It got pretty quiet after that burst of discussion. In my listening I've heard a bunch of WSPR, some CW, some other digital modes, and even an LSB qso! So there is some life below the broadcast band.

BTW, I think I've sent off my info to the UTC folks 4 times now, twice from the old address, and twice from the new and heard back NADA. No news is good news I'm told.

Clark, did your tube rig ever get on? KLC, did you ever get on down there?

Logged

73 de Kevin, WB2EMS
N4LTA
Contributing
Member
*
Offline Offline

Posts: 1075


« Reply #47 on: January 02, 2020, 04:44:33 PM »

I had several experimental licenses several years ago and regularly operated from 60 KHz to 500KHz. Class D transmitters are what I used at powers from 100 to 2000 watts. I used a 65 foot top hat vertical fed with large variometers. On 500 KHz standard CW was easy to accomplish for thousands of miles. My best 60 KHz was about  100 miles. It was so difficult I didn't continue for long. On 60 KHz the variometer coil cor was 36 " plastic pipe.

It is not a low power venture.  power MOSFETs make Class D transmitters easy to build and test.

One of my licences allowed AM, but I new got around to trying it. Would have been easy with a PWM power supply.

The first night that I operated on 498 KHz at 100 watts (transmitter build on an 8 x 5" Hammond chassis) - I kept quiet about it. I was amazed to get 10-15 messages on the experimental board asking who I was. Was lots of activity then. I am not sure about now. 7 KHz and the low EIRP sort of made me lose interest. I still have that little 100 watt transmitter and the HP signal generator locked to GPS though.

Pat
N4LTA
Logged
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #48 on: January 03, 2020, 02:58:22 PM »



Last night I verified I could get between 1-15 watts out of the ANAN cleanly through the LPF, without excessive current draw, so I put it on the air at 5 watts to see if anyone heard me.

Here's the plot for the last 24 hours. Whoo hoo! I was only on for about an hour last night around 11:30 pm, didn’t feel comfortable leaving it running unattended overnight yet, and only made about 6-7,  2minute transmissions.

 

About 35 station. Not too shabby! On the listening side I was hearing about as many, including two from across the pond in the UK and some from the pacific northwest! Pretty cool! This was with 5 watts to the antenna. Now I have to figure out how to estimate the EIRP from my low low dipole and see how much more power I can add to the antenna to see if I can stretch that out some. Doing a simulation with EZNEC my antenna gain is about -16 db, so I have some headroom to add power, up to about 200 watts, but not much more power available from the ANAN as it is.

Below is the coverage this morning around 8 am when the sun was up and the D layer is active. One two minute transmission. Tonight I’ll see if I can make any contact with FT8 or other modes.

73 de Kevin, WB2EMS



 




* 630 meter initial WSPR trial.jpg (179.46 KB, 1311x577 - viewed 283 times.)
Logged

73 de Kevin, WB2EMS
WB2EMS
Contributing
Member
*
Offline Offline

Posts: 633



« Reply #49 on: January 03, 2020, 03:03:24 PM »

Quote
The first night that I operated on 498 KHz at 100 watts (transmitter build on an 8 x 5" Hammond chassis) - I kept quiet about it. I was amazed to get 10-15 messages on the experimental board asking who I was. Was lots of activity then. I am not sure about now. 7 KHz and the low EIRP sort of made me lose interest. I still have that little 100 watt transmitter and the HP signal generator locked to GPS though.

Pat
N4LTA

Hi Pat,

I'm not sure how much activity there is down there these days besides WSPR yet either. I did see some sort of back and forth stuff going on lower in the audio passband, and there was some sort of FSK CW signal, but when I tried to copy it was all gibberish to me. It was also later in the evening, so activity on a weeknight might have already been down.

I think the low EIRP is an issue, but with realistic antenna efficiencies, most stations aren't going to get a lot more than 5 watts even with serious power. Lowfer folks have been doing interesting stuff for a long time with less.

We'll see how the next few weeks go. If I can  make some QSO's my interest will likely keep on. If not much out there besides WSPR, than it will fade. Still it was an interesting low effort exercise costing only $25 of electric fence wire and a few hours of pushing through brush.

Logged

73 de Kevin, WB2EMS
Pages: 1 [2] 3   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.09 seconds with 19 queries.