Topics

Thinking of selling FDM-S2 and getting DUO-R

Shaun Vincent Hopkins
 

Hi,
 
I'm thinking of selling the S2 and getting a Duo-R. Are there any pro's or con's to this? I'm old enough that I like real radio's with knobs on. SDR's are fantastic but the feel of a perfectly balanced wheel spinning through the bands will never leave me :-)
 
In GBP £ what's the rough value of an S2?
 
73's
 
Hoppy
 

 

Looks like they complete on eBay for £260, also one for sale for £260

Why not fill a trade in form at ml and s and see what they give u trade in 
Regards

Iain

On 23 Aug 2019, at 20:59, Shaun Vincent Hopkins <zbz5@...> wrote:

Hi,
 
I'm thinking of selling the S2 and getting a Duo-R. Are there any pro's or con's to this? I'm old enough that I like real radio's with knobs on. SDR's are fantastic but the feel of a perfectly balanced wheel spinning through the bands will never leave me :-)
 
In GBP £ what's the rough value of an S2?
 
73's
 
Hoppy
 

antennacrafter
 

Hoppy,

A perfectly balanced wheel isn't how I'd describe the tuning dial on a Duo. As a matter of fact, it one of the few things on a Duo that disappoints me. 

Bob


On Sat, Aug 24, 2019, 10:06 AM MM6IXE <sota@...> wrote:
Looks like they complete on eBay for £260, also one for sale for £260

Why not fill a trade in form at ml and s and see what they give u trade in 
Regards

Iain

On 23 Aug 2019, at 20:59, Shaun Vincent Hopkins <zbz5@...> wrote:

Hi,
 
I'm thinking of selling the S2 and getting a Duo-R. Are there any pro's or con's to this? I'm old enough that I like real radio's with knobs on. SDR's are fantastic but the feel of a perfectly balanced wheel spinning through the bands will never leave me :-)
 
In GBP £ what's the rough value of an S2?
 
73's
 
Hoppy
 

Shaun Vincent Hopkins
 

Thanks Bob, I'll see if I can get a hands on test. That's a shame really, as I do like a heavy balanced tuning wheel.
 
@ Iain, Thanks for the info. I don't think I've seen any on Ebay unless I've had bad timing!
 
Couldn't bring my S2 to France this time as I flew, no problem when I drive down.
 
73's
 
Hoppy
 

 
Sent: Saturday, August 24, 2019 at 4:26 PM
From: "antennacrafter" <leschyna@...>
To: EladSDR@groups.io
Subject: Re: [EladSDR] Thinking of selling FDM-S2 and getting DUO-R
Hoppy,
 
A perfectly balanced wheel isn't how I'd describe the tuning dial on a Duo. As a matter of fact, it one of the few things on a Duo that disappoints me. 
 
Bob
 
On Sat, Aug 24, 2019, 10:06 AM MM6IXE <sota@...> wrote:
 
Looks like they complete on eBay for £260, also one for sale for £260
 
Why not fill a trade in form at ml and s and see what they give u trade in 
Regards
 
Iain

On 23 Aug 2019, at 20:59, Shaun Vincent Hopkins <zbz5@...> wrote:
 
Hi,
 
I'm thinking of selling the S2 and getting a Duo-R. Are there any pro's or con's to this? I'm old enough that I like real radio's with knobs on. SDR's are fantastic but the feel of a perfectly balanced wheel spinning through the bands will never leave me :-)
 
In GBP £ what's the rough value of an S2?
 
73's
 
Hoppy
 

 

 

 
 

Ad Dieleman
 

I'm also considering to get a DUO-R instead of the FDM-S2 to get rid of the PC's QRM on a nearby loop antenna. Is the DUO-R generating QRM on a loop nearby at say 1 m distance? I'm primarily interested on MW reception. Thanks.

Ron Liekens
 

Ad, My logic tells me when you have a specific problem, you have to tackle that problem, not bying another radio wher you could switch of the computer. You write that you are interrested in MW reception. This branch of the hobby has need for a computer to get the most out of it, if youre really serious that is. The SDR will have to make I/Q recordings with a pc and write it to a HD.

I agree the Duo-R can do this also, but for this there is Always a computer needed for the job. So see why your computer is making qrm. If it is a lapotop or notebook the external power supply can be causing havoc and is easily cured. There are solutions available to silent a computer and you can save investing in a unneeded cost. I'm shure you will make the right decision.

Good luck,
Ron - ON2RON 

Uwe S.
 

Do not hope, the knob of the DuoR is so bad, you think it would be broken, but the DuoR a wonderful device.

Ad Dieleman
 

Thanks Ron, I have already experimented a bit to get rid of the PC's QRM but haven't been too successful so far.

AndersH
 

Ad, Ron,

I purchased a fresh PC battery to my HP laptop that allows me to listen and make recordings for around 2 hours without recharging. It's a bit primitive, but it kills the majority of my own noise.
Maybe a linear adapter is better, even if I have to make one myself.

Best regards,
Anders H.

Alain Reiner
 

Hello Ad, Ron, and Anders,

I had a lot of noise using a desktop PC. I tried to find if it was from ground loops (with USB cables) and never found out.

I migrated my Ham applications ( HRD, FDM-SW2, HDSR, etc...) to my laptop and I won between 6 and 10 dB on the QRM, with the laptop powered. I wanted a full HD screen, so it's a Gigabyte Sabre 17 with its genuine power supply. It's not the best on the category, you should find others without (power) noise.

Best Regards,
Alain F4HFS

Le 26/08/2019 à 12:11, AndersH a écrit :
Ad, Ron,

I purchased a fresh PC battery to my HP laptop that allows me to listen and make recordings for around 2 hours without recharging. It's a bit primitive, but it kills the majority of my own noise.
Maybe a linear adapter is better, even if I have to make one myself.

Best regards,
Anders H.

-- 
Alain Reiner

Shaun Vincent Hopkins
 

I have an HP 8770W, that does put out noise when the SDR is too close to the HD screen. Massive drop off in noise if I run on battery alone and I have an extra one for 5 - 6 hours run time.
 
I've found on my travels that Tanzania 220v in hotels is so noisy I gave up on MW DX even with magnetic loops. Dirty, dirty mains power.
 
Boston, Ma, exactly the same, dirty, noise power. Power cut during the snow and the band appeared! Normally too noise to do any dxing at all even with mag loops.
 
Might be a good idea to make a list of noise generating laptops and whether it is the display screen or PSU. I had a maplins psu that wiped out my whole LW/MW and into HF bands. Chased it down with an old transistor radio and then replaced all the noise psu's in my house. Much better now.
 
73's
 
Hoppy
 

 
Sent: Monday, August 26, 2019 at 9:00 PM
From: "Alain Reiner" <alain@...>
To: EladSDR@groups.io
Subject: Re: [EladSDR] Thinking of selling FDM-S2 and getting DUO-R
Hello Ad, Ron, and Anders,

I had a lot of noise using a desktop PC. I tried to find if it was from ground loops (with USB cables) and never found out.

I migrated my Ham applications ( HRD, FDM-SW2, HDSR, etc...) to my laptop and I won between 6 and 10 dB on the QRM, with the laptop powered. I wanted a full HD screen, so it's a Gigabyte Sabre 17 with its genuine power supply. It's not the best on the category, you should find others without (power) noise.

Best Regards,
Alain F4HFS

 
Le 26/08/2019 à 12:11, AndersH a écrit :
Ad, Ron,

I purchased a fresh PC battery to my HP laptop that allows me to listen and make recordings for around 2 hours without recharging. It's a bit primitive, but it kills the majority of my own noise.
Maybe a linear adapter is better, even if I have to make one myself.

Best regards,
Anders H.
 
-- Alain Reiner
 
 

 

I'm using Ferrite Clamps on all cabels. Power supply, Radios, Elad FDM-S2 ecc...
My noise is nearly zero. Even with the FDM S2 near the PC-BOX and places on top of the Power Supply as you can see.

A part i'm using then MFJ Deluxe Noise Cancelling Signal Enhancer just with the supplied extendible Antenna that is reducing always the noise in particular with the AM Broadcast stations. For upto 30 Mhz Amateur Bands very useful.
Also the MFJ-781 Data DSP Filter is very useful and efficient.

For a Home Station this should be done or similar.

Raimund
.

Neil Smith G4DBN
 

I use self-adhesive copper tape stuck to the back of the monitor, with holes for ventilation, then I solder wires to the tape and connect that to ground. The power lead has eight turns through a toroid.  The signal lead is wrapped with aluminium foil along with a drain wire, then that is taped to the lead and grounded.  All grounds are taken to a single point.  I also have lots of ferrite clamps, but they don't seem to help much. On the PC case, I have fitted additional bonding wires to ensure the PC case is solidly connected to the chassis. It is a newver-ending battle against noise.

The 2 inch copper tape I use is designed to repel slugs and snails to stop them climbing the sides of plant containers.

Neil G4DBN

On 27/08/2019 13:05, Raimund wrote:
I'm using Ferrite Clamps on all cabels. Power supply, Radios, Elad FDM-S2 ecc...
My noise is nearly zero. Even with the FDM S2 near the PC-BOX and places on top of the Power Supply as you can see.

AndersH
 

Alain:
I agree that keeping one's PC and essential peripherals "concentrated" in a small physical volume, separated from the radio, helps,

Hoppy,
On paper, most AC adapters should be compliant with FCC and EN EMC requirements, but it seems that HP and Dell mainly worry about fire hazards and electrical isolation hazards, even though there are relatively strict electromagnetic emission requirements in place for these devices. I think it's good to list bad adapters whenever we stumble across them.

Raimund,
Ferrites help against common-mode noise, they are not quite as efficient for differential-mode noise.

Best regards,
Anders H.

Ad Dieleman
 

Thanks for all the advice, some things there I didn't try yet, so there's hope for improvement.

 

Anders H.,

i agree with you. Anyway i would like to point out that the noise can be reduced quite a lot.
I'm not using portable PC's, only BOX Pc assembled with a very low interference. A ready industrial product is never the same.

A portable PC might be useful but never like a real assembled BOX PC.

Raimund
.

AndersH
 

Hello again Raimund,

I fully agree with your comment. Just as a curiosity, there is a third "flavor" of PC:s that might be inherently silent. Field laptops certified against MIL-STD-461E. The older Panasonic Toughbook CF 31 MK IV was built like a tank and perhaps built to be used in a tank too. :-)
https://snebulos.mit.edu/projects/reference/MIL-STD/MIL-STD-461F.pdf

Anders H.

Shaun Vincent Hopkins
 

 
There was once a TEMPEST proof laptop when I was in the military and it was over £10,000 back in 1996! I can't remember anything about what type it was - but I'll never forget the price tag! You could by a house with 5 of those back then ;-)
 
73's
Hoppy
 
PS. Thanks for the other info guys. I'll be putting new earth / grounds into my shack before the winter DX season
 
 

Sent: Thursday, August 29, 2019 at 1:14 PM
From: "AndersH" <anhn@...>
To: EladSDR@groups.io
Subject: Re: [EladSDR] Thinking of selling FDM-S2 and getting DUO-R
Hello again Raimund,

I fully agree with your comment. Just as a curiosity, there is a third "flavor" of PC:s that might be inherently silent. Field laptops certified against MIL-STD-461E. The older Panasonic Toughbook CF 31 MK IV was built like a tank and perhaps built to be used in a tank too. :-)
https://snebulos.mit.edu/projects/reference/MIL-STD/MIL-STD-461F.pdf

Anders H.
 
 

Shaun Vincent Hopkins
 

I bought one, £599 :-D Bonus! Won't get to play with it as I'm away from home at work and it arrived 3 hrs after I left for work. Can't wait to try it and see how it is to use.
 
I was hearing 590 VOCM clearly and other transatlantics on my home antennas at 0545 this morning. I'm glad I did my antenna maintenance.
 
73's
Hoppy