Messages

136

SDR - Software Defined Radio / Re: SDR recommendation......

« on: September 06, 2020, 1455 UTC »

Copied from my rely in another thread....

The RX-666 and RX-888 are similar. Both are based on the BBRF103 open-source design. The RX-888 adds an integrated LNA, plus claims of possibly a higher-precision TXCO, for around $200 to $250 from China via eBay or similar.

For HF and below, both appears to use the LTC2208.... or a clone.... or a salvage chip? The LTC2208 is 15 years old at this point, but AFAIK, it still is not a cheap IC to legitimately source new. Up to 32MHz sampling, with up to 28.8MHz alias-free sampling. USB 3.0 is required for such high sample rates.

BTW, above HF they use a common R820T2, but apparently with up to 8MHz sampling currently possible.

----------------

About software, AFAIK there is a modified version of HDSDR+EXTIO for the RX-666, plus I have seen a claim the BBRF103 project EXTIO should work. I have no idea if either supports configuring the LNA in the RX-888, though.

More:
https://dk8ok.org/2020/09/04/rx-888-32-mhz-16bit-200-us-pricks-up-your-ears/

This is starting to look interesting.

137

Equipment / Re: Ideal height and polarisation of MLA30 for best DX performance?

« on: August 31, 2020, 1253 UTC »

Managed to pick up a rare DX with the MLA30+ last night albeit very weak signal, I could hear it.

It is Radio Logos from Peru Txing with 1 kW and distance from me is 12,000 km. Not bad with a 29 Euro active loop antenna

https://twitter.com/Radio0Play/status/1300372125673549824

Hopefully you actually had an ID.  Your Twitter video posting had no intelligible audio.

138

The RF Workbench / Re: Inexpensive frequency counter Modules

« on: August 28, 2020, 1151 UTC »

I don’t know which frequency counter module you have, but if it is similar to this one, it does have an adjustment for the counter timebase.

https://www.mpja.com/Frequency-Meter-6Digit-100KHz-65Mhz-Blue/productinfo/35059+TE/

139

General Radio Discussion / Introduction to ACARS

« on: August 14, 2020, 2035 UTC »

From Defcon 28:

https://youtu.be/NFS6qNAi0B8

140

General Radio Discussion / TURMS TECH LLC

« on: August 14, 2020, 1143 UTC »

Who are these guys?  They are associated with WIPE, the new HF station in Alpine, NJ, and seem to be connected with the station in Matavia, IL.

A google search on them pops up a lot of stuff.

Also look at the FCC page for items associated with them.  The latest posting includes the
following as operating frequencies:

9.650 MHz
11.850 MHz
13.720 MHz
15.450 MHz


https://fcc.report/IBFS/Filing-List/IHF-LIC

141

Equipment / Re: IC-7300 as a SWL receiver

« on: August 09, 2020, 1408 UTC »

Icom has a long history of announcing radios a year before they are available, but the virus has made this delay exceptionally long.

$1433 list and a street price of $1300 seems high, particularly when you look at what the IC7300 and IC9700 sell for.  When the IC705 was first announced, the guesses on price were on the order of $800.  The Elecraft KX3 is $1200 but lacks 144/440, the panadapter, and DSTAR, so I can see what the Icom marketing department must be thinking.

142

Equipment / Re: IC-7300 as a SWL receiver

« on: July 29, 2020, 1122 UTC »

Those are all very good points.  The IC705 may in fact end up as the best choice as an SWL receiver.  Icom know they have a winner so demand (and prices) will be high for a while.  The IC7300 street price was $1500 when it first came out, eventually hit a low around $800, and is back up to around $1000 today.  While the IC705 seems to be starting out a lot higher in price than was first expected, those who wait may reap significant savings.

At Contest University in 2017, Bob Sherwood said 10,000 IC7300 radios had been sold.  A few years later it had doubled.  Is this the most popular radio ever?  I don’t know.

https://www.contestuniversity.com/wp-content/uploads/2017/06/NC0B_CTU_2017_Disruptive_Technologies_How_they_Change_our_Hobby.pptx

It’s pretty hard to buy a new radio today that is a poor performer.  The performance differences between the high end radios are pretty much at the point that they can only be seen in laboratory tests.  Even the $100-200 SDR radios deliver more performance than most can use.

I hear you about the problems in buying early ThaDood. Been there too often myself!  Sometimes a firmware change is all that is necessary, but on more than one occasion I have had to send a radio back to the factory to have them install a physical update to the radio. 

We will see if I have sufficient will power to wait long on the IC705...

143

Equipment / IC-7300 as a SWL receiver

« on: July 28, 2020, 1338 UTC »

Recently I was looking at a used Icom R75 receiver that was for sale at Universal Radio.   I realized that while the price was roughly about half the price of a brand new Icom 7300 transceiver, the 7300 had the water fall display and didn’t need any additional hard to find filters.  I have a 7300 I use for day to day ham activities and I am happy with it.

N9EWO recently posted a review of the 7300 as a SWL receiver here:
https://www.qsl.net/n9ewo/ic7300.html

The IC7300, even with its recent price increase, has to be one of the best values in ham/swl radios available.

144

Equipment / Re: Quick and dirty 434 MHz 8 Element Yagi

« on: July 24, 2020, 1226 UTC »

This reminds me of the “2 meter beam for 2 bucks” in the Nov 1971 issue of Electronics Illustrated.  It was a simple beam using coat hanger wire for elements and a simple coax balun on a wooden mast.  It actually worked and was perfect for a cash poor teenage ham.

You might want to try coat hangers for elements rather than electrical wire.

145

General Radio Discussion / FCC action against pirates

« on: July 15, 2020, 1349 UTC »

https://www.lexology.com/library/detail.aspx?g=15af862d-825a-410d-a8ed-3c5c74442b03&fbclid=IwAR0-814qM79lxZfv4kFqzo7t_2SBVOsyfp3KT5DUAVMMR22D5vt64rb5RSc

“Wilkinson Barker Knauer LLP
David Oxenford
USA July 13 2020

Pirate radio operators continue to be a problem – particularly in major metropolitan areas. The week before last, the FCC resolved two long-pending cases against pirate operators through negotiated settlements. In one case, the FCC last year initially proposed a fine of $151,005 for the illegal operation. After examining the operator’s finances, the Bureau agreed to a $4,000 fine now, with a penalty of $75,000 should the operator violate the law again (see this decision against an operator called Radio Concorde). In the second case, the FCC had proposed a $453,015 fine last year, but agreed to take $5,000 now, with penalty of $225,000 if the operator violates the terms of the consent decree (see the decision dealing with operator Radio TeleBoston). Last year, we wrote here about the much larger fines initially proposed for these two operators.

In both cases, the FCC seemingly recognized reality in taking the small upfront payments now rather than trying to collect huge fines that likely were beyond the ability of the operators to pay. The FCC also required the surrender of the operator’s equipment and a commitment to stay away from pirate radio for 20 years or face much larger fines. The big fines initially imposed in these cases were set even before Congress enacted the PIRATE Act early this year. The new law allows for fines on illegal operators of $100,000 per day, up to a maximum total fine of $2,000,000. Even without the full effect of the PIRATE Act, these cases show the deterrent effect of these large fines. They get an illegal operator’s attention, which can lead to the shutdown of these unauthorized stations, as happened in these cases. With the pandemic, we worry about even more illegal uses of the broadcast spectrum – and we will write more about that issue here tomorrow.”

146

General Radio Discussion / Re: Proposed Shortwave Station in Illinois Prompts an Objection

« on: July 15, 2020, 1244 UTC »

I can't see how this is going to be fast enough for trades.  Most Data Center locations are based on fiber latency and it used to be in Milliseconds Now It's in Microseconds. it won't be long until it's in Nanoseconds. Even Microwave would be faster for trading.. So there must be something more to it.

tAC

Raft Technologies claims “milliseconds of advantage between exchanges oceans apart”.  Signals that travels through a medium like fiber or processing equipment will do so at “slower than the speed of light in a vacuum”.  The radiowave path is traversed at the speed of light.  Latency accumulates, so the more equipment and fiber they can cut out of the path by going direct, the greater the possible advantage. 

147

General Radio Discussion / Re: Proposed Shortwave Station in Illinois Prompts an Objection

« on: July 14, 2020, 1222 UTC »

15 KW seems low for a serious SW broadcaster.  But maybe not inappropriate for a HFT data broadcast using log periodic beams for a point to point circuit.

Are DRM transmissions low enough latency to be consistent with high frequency trading requirements?

I’ve wondered what part of the FCC rules they were going to apply for a license under.  They certainly aren’t aeronautical or maritime and an experimental license no longer worked once they became operational.  Maybe this is their path.

148

Equipment / Re: The Best Active Loop Antenna 2019 = MLA-30?

« on: July 11, 2020, 1416 UTC »

Well said Chris!

You have to take most of these product reviews with a grain of salt, particularly if you aren’t familiar with the reviewer.

And we all tend to hear what we want to hear in these reviews and ignore the rest.  The product reviews on eHam are a good example of that....or Amazon product reviews...  A significant amount of those are just “noise” and deserve to be ignored...or from people with an axe to grind...

As Chris points out, too little attention is spent on the environment that the reviewer is in.  If his local RF noise level is high, then a product that has a low SNR may be indistinguishable from one with a high SNR.  Or if someone lives on top of a mountain with low horizons in all directions, then most any antenna is going to deliver a lot of stations.

149

General Radio Discussion / Re: Russian Kerosene Powered Radio

« on: July 07, 2020, 1307 UTC »

They aren’t kidding about these people being sick or even dead.  The LD 50/30 rule of thumb is that a dose of 400 to 450 REM in a short period of time will cause death within 30 days for 50% of those exposed.  If those sources were radiating at up to 1000 Roentgens, they picked up a significant dose while stripping them for metal.

150

General Radio Discussion / Re: RPi based ham radio wall clock

« on: June 21, 2020, 1200 UTC »

Gigaparts is selling a prepackaged version of this clock for an insane amount of money ($300).  You are starting to get into the realm of the Geochron cost.  Much cheaper to role your own...

https://www.gigaparts.com/veritium-hfclock-pi.html


BTW, one of the local hams made a similar comment about CSI’s astronomy software.  He said they produce good products.