eHam Forums => Station Building => Topic started by: K0AST on November 04, 2003, 02:58:09 AM

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: K0AST on November 04, 2003, 02:58:09 AM
If you had to choose, which would it be and why?



Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: VE3TMT on November 07, 2003, 07:58:01 PM

TS850 is a much more solid radio than the 870. Wish I never got rid of mine. Only downside is you pay almost as much for a used DSP100 as you do for the 850.  Much be a cheaper investment to pick up a mint TS870.

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: K8AC on November 10, 2003, 03:44:50 PM
I think you'd be disappointed with the DSP-100 on the TS-850.  Go with a later model TS-870.

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: NI0C on November 16, 2003, 09:03:31 PM
The DSP unit for the TS-850S is an audio unit, while the TS-870S uses IF DSP built-in.  If you are serious about CW operation, I'd recommend the 850 with filters of your choice, plus an outboard audio DSP filter (not necessarily the DSP-100).

I've used a TS-850S for nearly seven years.  After re-reading the QST reviews of the 850 and 870, I wouldn't trade mine for the 870. QST points out that CW reception of the 870 is compromised by the lack of narrow analog filter at the second I.F.

I'm currently using a 250 Hz INRAD filter in the second IF, followed by a 500 Hz Kenwood filter in the third IF.  For audio filtering, I use the MFJ484B, which is excellent.  

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: VE3TMT on November 16, 2003, 10:55:22 PM
To the previous poster,

You might want to go back and read the brochure for the DSP100.  It is definitely NOT an audio DSP unit. It plugs into the IF chain in the 850.


Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: NI0C on November 17, 2003, 08:25:56 AM
I got my information from QST's review of the TS-850S, (July 1991 QST).  On page 45, under the heading DSP-100 Digital Signal Processor, the article states, "... the DSP unit provides receiver-audio filtering and transmitted-signal processing ....).  The article concluded that the unit was of "limited practical value" in this regard.  

I don't think Kenwood sold many DSP-100 units.  I've only seen one used one at a hamfest (Dayton, a couple of years ago).  I almost bought it, but it had been rained upon!

Tell us what Kenwood claims about this product-- perhaps the QST article was incorrect.

73 de Chuck  NI0C

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: JAMES_BENEDICT_EX_N8FVJ on November 19, 2003, 10:10:03 AM
DSP aside, the TS-850S outperformed the TS-950 series. The TS-870 is a marvel of high tech engineering, but the lastest version with all the updates is needed before comparing to the TS-850S.

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: VE3TMT on November 20, 2003, 02:49:08 PM
I think what the article is stating is misleading.  The DSP100 does provide audio tailoring, but it is done at the IF level.  Same applies to the transmit side.  What the DSP100 does is tailor the transmit and receive bandwidths inside the 850.  On the receiving end there will be a difference, in which some may perceive as an audio, which it is, but it isn't like a mic equalizer which alters the audio response going into the radio.  Also back in 1991, hifi SSB didn't exist.  When the DSP100's came out, that was not there intended purpose.  Just over the last couple of years hams have found out how to make these really make your audio sound good.  Of course they are still using equalizers and other audio gadgets,  because no matter what frequency curve you put into the rig, it will only be as wide as the widest filter. I regularly see the DSP100's selling for upwards of $5-600 US. Back in 1991 they were selling for $650 new.  These are highly sought after items. One my previous 850 I ran a studio mic & parametric eq, but no DSP100.  It sounded pretty good.  I have another 850 on the way, and if I was to find a DSP100 at an attractive price, I wouldn't hesitate to pick it up.

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: WB5UAG on November 20, 2003, 08:57:08 PM
I have one TS-850 with the DSP-100 and another without the DSP-100.  Like another poster, I'd buy another DSP-100 if I could find one at a reasonable price.  The TS-850 has been the best ham rig I have ever owned, that's why I won two of them.  I have used one of my rigs as my mobile.  It made my vehicle pretty crowded but I had a great rig.  I have since bought a good mobile rig.  

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: NI0C on November 21, 2003, 01:44:01 PM
Thanks for the response.  I agree that 500-600 U.S. dollars is too much for the DSP-100.  Perhaps I should have taken a chance on the one I saw at Dayton.  The guy was asking only $125 for it.

73 de Chuck  NI0C

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: VE3TMT on November 22, 2003, 03:05:10 PM
$125!!!  I would have snapped it up so fast, provided nothing was wrong with it.

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: W7MD on December 09, 2003, 05:14:37 AM
I purchased a brand new TS-870 about 1 year after they were released. It replaced a Yaesu FT-1000D which had audio which was harsh and unpleasant to my ears. I found the TS-870 to be an excellent SSB radio but less than useless as a CW rig. The continuously variable bandwidth (in DSP) was a thing of wonder for SSB.
In a CW contest, my TS-870 was unable to separate closely spaced signals. I asked about modifications but was told by Kenwood reps that there were none.
I then bought a Yaesu 1000MP which I use continually at home. It is an excellent radio for SWB and CW.
I sold the TS-870 to a local ham who is not a CW operator after allowing him to take it home and use it for a while.
I then bought a nice used TS-850SAT from a local ham and added the 500 kHz CW filter.  This radio is the best CW radio I have ever used.  The cascaded filter setup is outstanding.  I worked some of the CQ WW DX CW Contest last week from a portable location using a St Louis Vertical antenna. There was no signal that I could not separate from it's neighbor even though I was using an omnidirectional antenna.
Under no signal conditions, the TS-850 receiver is quieter than my 1000MP.
The TS-850SAT built in tuner does not tune the received signal which is a problem if you are using a non resonant antenna.  You can use a external tuner to overcome this deficiency.  I understand that the tuner receive control can be added with a modification.
Neither the 850 or the 870 has an input connector for a separate receive antenna such as a Beverage. This can be added.
The 850 has a 20+ DB receive attenuator in the broadcast band which will bug you if you want to listen to broadcast AM.
When working split frequency DX, I prefer a 2-knob tuning radio which can listen to the receive freq and transmitting frequency at the same time - like the 1000MP can.  But the MP with it's built in AC power supply is a heavy load to lug and the 1000D was worse.
I find the TS-850 perfect for portable work. It is light and gives you the option of working off a battery if you choose. It is also relatively inexpensive on the used market.
I also have an Icom 706 MarkIIG which I use mobile but I find that,like the 870, it is not a good radio for pulling CW sigs out of a pile.
I hear that some modifications were made to improve the CW capabilities of later model TS-870s.
I do have the DSP-100 unit which I may use for operating AM with the 850.  I have not found much use for the DSP-100 in my situation as I use the 850 for portable operation and the DSP-100 addon is just another thing to carry and a bunch more cables to hookup.
Damon, W7MD

Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: WA2JJH on December 18, 2003, 07:45:03 AM
Unless you got the $125 bargain at dayton, it would be hard to justify the price. If you can live without DSP,
the TS-850 dual switchable IF's rule. The TS-850 has the better RCVR.

  The current TS-850 used price is about $700. The TS-870 cost's more than double that.  IHMO I would save the money.
Invest in having all the dual stage xtal filtering in the TS-850.
  Some have also complained about not having manual notching in the Ts-870 as well. The auto-notch can be fooled.
 I own a TS-850. I tried the TS-870. As others noted the TS-850 feels more rugged.

  How many times have you seen this review..., owned the TS-850. Worked great...sorry I sold it!
Sorry I cannot give you a direct DSP-DSP comparison.
DSP does not impress me.


Title: TS-870 v. TS-850 w/DSP-100 comparisons?
Post by: WA7NCL on May 10, 2004, 12:03:56 PM
Choose the TS-870.  The use of audio add on DSP is always inferior.  The reason is the AGC in the 850 with external audio DSP will be pumped by signals inside the IF (non-DSP) filter.  If the interfereing signal is stronger than the weak one you are trying to select, the AGC will turn down the RF gain to the point that the recovered audio from the weak signal will be very small.

I own a TS870.  The IF dsp is awesome for CW.  Selectivity down to 50Hz with AGC adjustable time constant and AGC derived from the single in band signal.  If you are a CW op you will not be disappointed.

For PSK 31, you can modify the RCP95 radio control software to allow use of the CW filters on recieve and correct for the offset (on CW).  I do this a lot and it results in single signal reception for PSK.  You can work PSK signals down to a level it would be hard to even copy as CW.  50Hz filtering on PSK is awesome.

There you have my two bits.