Kenwood TS850s vs Yaesu FT920 Test in banda de 80m
Kenwood TS850s vs Yaesu FT920 Test in banda de 80m
Some recent pictures of my radio shack. You can see the old Kenwood TS850s, the audio Behringer rack that contains Behringer Feedback Destroyer DSP1224p, Behringer Dynamics Processor MDX 1600, Behringer Virtualizer PRO DSP2024p, Behringer B1 Studio Condenser microphone with DIY pop filter, Behringer Xenyx 802 mixer used as a preamp and my Proxel power supply.
With some help from Marius YO3HYR, I finally manage to connect the Kenwood TS850s AT to the computer on the CAT interface and also as a digital mode. Above you can see some photos of the wonderful work of YO3HYR interface.
Interfete CAT / Moduri Digitale pentru transceiverele ICOM, Kenwood, Yaesu pot fi comandate prin intermediul HamShop sau direct la YO3HYR.
Last year I’ve told you about my first DRM (Digital Radio Mondiale) reception using a down-converter from the 36.891 khz TS850s DSP2 FI to the 12Khz signal necessary for the PC sound-card. Well, this is the final version of the module, now all in one nice box. 😀
Everybody knows the fact that Kenwood TS850s is a great transceiver but unfortunately at the-same time this rig is at least 13 years old.
One of the electronic component type that has problem with age are the electrolytic capacitors contained in the transceiver. By the passing of time, due to leakage, electrical stress or heat exposure the characteristic value of those components can be changed.
To obtain the best result, and prolong the transceiver life I guess is a good idea to replace all the electrolytic capacitors inside my TS850s.
According to an eBay post, there are 113 small electrolytic capacitors used in the TS850s. The price (39USD) is a bit high so I’ll acquire them from a local electronic part store.
So, we need:
Finally I did it! Using the idea of EA1GHE and my Kenwood TS850s I can listen now DRM Digital Radio Mondiale stations. If you got a Kenwood TS850 you must build the down-converter and connect it to a PC with a good sound-card (I use the old SB Live but it seams that is working also on my HP 530 Laptop) and on the other side, connect the converter board also to the DSP2 plug.
Powering up the transceiver keep the F.Lock button pressed to enter a setup menu. Tune with the M-CH./VFO.CH knob at menu 5, turn it on by pressing the Up/Down keys and after that turn off the rig and back on. You will not have sound on you’re speaker in USB/LSB CW/FSK mode but you can hear the reception on AM/FM mode. To come back at normal settings, proceed the-same steps but turn the menu 5 OFF.
To receive DRM you must set the transceiver to FSK mode, 12Khz filter on 455Khz FI and no filter on 8.83FI, AGC knob must be set to Slow, AIP and Noise Blanker must not be activated.
A good DRM frequency for testing is 13.810 Khz DW/BBC broadcast station. If you can’t hear anything there, check the DRM Frequencies list.
Have fun by listening hi quality digital radio on shortwave!
Kenwood TS850s Remote Connector Pinouts, solder side view.
1- Loudspeaker Output
2- RX-TX Relay Common
Yesterday at YO3KSR Radio-Club we’ve tried to listen some DRM (Digital Radio Mondiale) broadcast stations. Unfortunately it from different unknown it was not a success… I did some Google research on the idea of decoding DRM signals using my PC and the well known Kenwood TS850s. On EA1GHE blog there where a solution for the TS450 by connecting a mixer on the DSP2 rear connector that is able to convert from the 36.891 khz FI to the 12Khz signal necessary for the PC Sound-Card… More info about that you can see on EA1GHE web-page or on this PDF file.
PS: In the video above, you can see one of the DRM station listen on my “analog” TS850s receiver.
Some of the equipment where changed some of them are still the-same. In the movie above you can see my precious Kenwood TS850s AT, the Behringer B1 studio mike, Behringer’s Shark DSP110 (noise-gate and mike preamp), Behringer Feedback Destroyer Pro DSP1124p (12 band parametric eq), Behringer Ultramizer Pro DSP1424p … and other stuff…
I know that you probably believe that I’m into eSSB but actually I’m transmitting on the 2.7Khz filter. The difference with those audio equipment is that on the ~50hz – 2.9Khz bandwidth the modulation is sounding great, much better then the MC43 default mike.
In the post before I’ve told you about the classic ALC problem that my TS850s also encounter. The solution was simple, R2 and R3 on the DC/DC board must be changed from 22K to 18K. The two resistors are SMD so it’s very hard to work on them that’s why my solution was to mount in parallel with those, ordinary non-SMD 100K resistors to reach the value around 18K as recommended.
Well now everything works just fine. I’ve got proper ALC reading on all band with 100W output without any problems.
Damn, the old lady Kenwood TS850s is doing some problems again. I guess the ALC DC/DC Board is the problem. Above you can see a movie with the phenomenon. Must study….
Am intercalat pe lantul audio al microfonului un mic montaj al carui scop este de a atenua iesirea de linie la nivelul intrarii de microfon si in acelasi timp realizeaza o decuplare galvanica eficienta intre Kenwood TS850s si restul echipamentelor audio.
Schema initiala apartine renumitului W2IHY dar un pic modificata conform necesitatilor de aici. Cu siguranta aceasta poate fi adaptata pentru a fi folosita si cu alte tipuri de transceivere.
JA7JLQ, Japan station in 40 m band, tonight around 23:15 local time, on my Kenwood TS850s. He was working with a Yagi Antena and 1KW output power.