NO84 in safe mode
Hi Bob, Yes me and Scott K4KDR has observed this both with NO-84 the past few days. Here is a video Scott has on youtube of NO-84's 70cm PSK31 downlink acting crazy https://www.youtube.com/watch?v=8XqcUNJumSE . The 70cm downlink has been either a ticking carrier, not transmitting at all, or will transmit properly for a few seconds before going crazy again. I hope this is not the last we hear of the PSK31 transponder as I have really enjoyed it. The APRS downlink with the beacon telemetry has been observed by both me and him as either off completely or on for a limited a time. I hope to see NO-84's condition improve soon and to see the launch coming up in a few weeks of NO-84s replacement, PSAT-2 on the next Falcon Heavy Launch!
73 - Nick KE8AKW
That sounded like some 1950's B Sci-Fi Movie!
But I do say what are you using to hear it with, awesome strong signal!
Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 6/10/2019 4:36 PM, Nicholas Mahr KE8AKW via AMSAT-BB wrote:
Hi Bob, Yes me and Scott K4KDR has observed this both with NO-84 the past few days. Here is a video Scott has on youtube of NO-84's 70cm PSK31 downlink acting crazy https://www.youtube.com/watch?v=8XqcUNJumSE . The 70cm downlink has been either a ticking carrier, not transmitting at all, or will transmit properly for a few seconds before going crazy again. I hope this is not the last we hear of the PSK31 transponder as I have really enjoyed it. The APRS downlink with the beacon telemetry has been observed by both me and him as either off completely or on for a limited a time. I hope to see NO-84's condition improve soon and to see the launch coming up in a few weeks of NO-84s replacement, PSAT-2 on the next Falcon Heavy Launch!
73 - Nick KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
... what are you using to hear it with, awesome strong signal!
Hi Joe! Yes, NO-84 has had an excellent 70cm downlink; I share everyone's hope that we will see it return to normal operation. When using the PSK31 transponder, the FM downlink on 435.350 has been nearly horizon to horizon when conditions were good.
My receive setup for that particular configuration was the 70cm X-Quad w/ SP-70 LNA on an AZ/EL rotator to the SDRPlay RSP1.
-Scott, K4KDR
========================
On Mon, Jun 10, 2019 at 6:28 PM Joe via AMSAT-BB amsat-bb@amsat.org wrote:
That sounded like some 1950's B Sci-Fi Movie!
But I do say what are you using to hear it with, awesome strong signal!
Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com
On 6/10/2019 4:36 PM, Nicholas Mahr KE8AKW via AMSAT-BB wrote:
Hi Bob, Yes me and Scott K4KDR has observed this both with NO-84 the past few
days.
Here is a video Scott has on youtube of NO-84's 70cm PSK31 downlink
acting
crazy https://www.youtube.com/watch?v=8XqcUNJumSE . The 70cm downlink
has
been either a ticking carrier, not transmitting at all, or will transmit properly for a few seconds before going crazy again. I hope this is not
the
last we hear of the PSK31 transponder as I have really enjoyed it. The
APRS
downlink with the beacon telemetry has been observed by both me and him
as
either off completely or on for a limited a time. I hope to see NO-84's condition improve soon and to see the launch coming up in a few weeks of NO-84s replacement, PSAT-2 on the next Falcon Heavy Launch!
73 - Nick KE8AKW
On 11/6/19 10:36 am, Scott via AMSAT-BB wrote:
My receive setup for that particular configuration was the 70cm X-Quad w/ SP-70 LNA on an AZ/EL rotator to the SDRPlay RSP1.
Is the RSP1 superior to rtl el cheapo $20 SDR dongles in regards to receive sensitivity? My experience with rtl dongles is that although I can hear strong signals they are nowhere near as sensitive as say a Chinese handheld radio.
Hey Phil.
I can only speak to the SDRPlay RSP1 and Airspy R2, but those are two of the SDRs available that are significantly superior to the basic RTL-SDR devices.
Many people use the premium SDRs such as these products for some really weak (and/or dirty) signal reception. The SDRPlay products are particularly good for full-duplex transponder use, too. For linear satellites, I use the SDRPlay RSP1 exclusively as my receive "radio".
Hope that helps!
-Scott, K4KDR
=======================
On Mon, Jun 10, 2019 at 9:43 PM Phil via AMSAT-BB amsat-bb@amsat.org wrote:
On 11/6/19 10:36 am, Scott via AMSAT-BB wrote:
My receive setup for that particular configuration was the 70cm X-Quad w/ SP-70 LNA on an AZ/EL rotator to the SDRPlay RSP1.
Is the RSP1 superior to rtl el cheapo $20 SDR dongles in regards to receive sensitivity? My experience with rtl dongles is that although I can hear strong signals they are nowhere near as sensitive as say a Chinese handheld radio.
--
Regards, Phil
In my uncalibrated-ear testing with an A/B switch on satellite downlinks, I found my RSP1A is noticeably more sensitive (with HDSDR driving it) than the FT-857D, FT-818ND, and the TH-D74A, and comparable (on 2 meters) to the KX3. While none of these are really proper satellite base station rigs, I have to believe all of these are better receivers than a $20 SDR dongle. The downside with the SDR is the almost one full second delay I experience in hearing the downlink, but I'm starting to get used to it.
73, Ryan AI6DO
On Monday, June 10, 2019, 6:42:58 PM PDT, Phil via AMSAT-BB amsat-bb@amsat.org wrote:
On 11/6/19 10:36 am, Scott via AMSAT-BB wrote:
My receive setup for that particular configuration was the 70cm X-Quad w/ SP-70 LNA on an AZ/EL rotator to the SDRPlay RSP1.
Is the RSP1 superior to rtl el cheapo $20 SDR dongles in regards to receive sensitivity? My experience with rtl dongles is that although I can hear strong signals they are nowhere near as sensitive as say a Chinese handheld radio.
On 11/6/19 12:44 pm, Ryan Noguchi via AMSAT-BB wrote:
In my uncalibrated-ear testing with an A/B switch on satellite downlinks, I found my RSP1A is noticeably more sensitive (with HDSDR driving it) than the FT-857D, FT-818ND,
Thank you Ryan and Scott for your replies. I'm surprised that the RSP1 is more sensitive than the FT-817, which I bought when they first became available.
I've been away from Amateur Radio for quite some time and I feel that advances in the field are passing me by.
On 2019-06-11 00:00, Phil via AMSAT-BB wrote:
Thank you Ryan and Scott for your replies. I'm surprised that the RSP1 is more sensitive than the FT-817, which I bought when they first became available.
I've been away from Amateur Radio for quite some time and I feel that advances in the field are passing me by.
Phil-
There is much information available to catch up on recent (and not so recent) advances. The author of Linrad has done some dynamic range comparisons:
https://www.youtube.com/watch?v=QbSa1G14Nig
Note that a receiver that is too sensitive may be easily overloaded by a strong signal, requiring an attenuator proceeding it and resulting in an increase in noise figure.
A less sensitive receiver that performs better on the "top end" when strong signals are present can be helped out with a switchable LNA at the antenna. Which is, of course, where the LNA should be to set the system noise figure. No strong signals and you need some more sensitivity, switch on the LNA.
https://youtu.be/_-AkINSPkhw?t=505
--- Zach N0ZGO
On 12/6/19 3:15 am, Zach Metzinger via AMSAT-BB wrote:
There is much information available to catch up on recent (and not so recent) advances.
Thank you Zach and Ryan,
I've recently renewed my interest in computer programming after practically no activity for the past 15 years; Amateur Radio is in the same boat. So much to catch up on and so little time left to do so.
I sold my FT-817 20 years ago because I wasn't making much use of it and bought an FT-847. AO-40 really had me excited for a couple of years but after its demise I slowly lost interest and the radio hasn't seen the light of day for a long time.
To be fair, my experience is only with the RSP1A, which is two years (two generations!) newer than the RSP1 that Scott uses. If you're looking to inexpensively add a receiver to a transmitting radio for a full duplex satellite system, the $120 RSP1A is a very serviceable option and much cheaper than a transceiver. I don't think the RSP1 is available new any longer.
You're right in that in certain portions of amateur radio, the equipment is evolving very quickly; in other areas, very glacially. I bought a new FT-818ND last year, which is not really a substantive improvement over the FT-817ND, which has been around for fifteen years. I use it exclusively as a transmitter for linear satellite work, and it works well in that role, as would your FT-817.
73, Ryan AI6DO
On Tuesday, June 11, 2019, 6:29:05 AM PDT, Phil via AMSAT-BB amsat-bb@amsat.org wrote:
On 11/6/19 12:44 pm, Ryan Noguchi via AMSAT-BB wrote:
In my uncalibrated-ear testing with an A/B switch on satellite downlinks, I found my RSP1A is noticeably more sensitive (with HDSDR driving it) than the FT-857D, FT-818ND,
Thank you Ryan and Scott for your replies. I'm surprised that the RSP1 is more sensitive than the FT-817, which I bought when they first became available.
I've been away from Amateur Radio for quite some time and I feel that advances in the field are passing me by.
participants (6)
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Joe -
Nicholas Mahr KE8AKW -
Phil -
Ryan Noguchi -
Scott -
Zach Metzinger