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Re: Is FT-857D basically the same as FT-897D
The original 857 (late 2002 or early 2003 introduction) did not have the DSP card standard, but it was an option.? Nor did the original 857 include 60m pre-programmed channels in the memory.? The 857D came out late 2003 or 2004 as I recall, and at least had the DSP card standard.? I have an original 2003 857 with the optional DSP card and without the 60m channels.? I also have a 2016 857D which has the DSP hard mounted and includes the five 60m channels in the memory.? Hope this helps.... de Cliff W3KKO Sent from AOL Mobile Mail On Tuesday, December 22, 2020 Leonard K. Pennock <[email protected]> wrote: There was both a D and non-D version of the 857 and 897. 857D included the audio frequency DSP that was optional on the 857. 897D got the txco and dsp. The 897 and 857 are identical circuitry in same generation. -- Leonard K. Pennock (AD7AS) On December 22, 2020 9:40:35 PM MST, Eric <eric@...> wrote:
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Re: Is FT-857D basically the same as FT-897D
¿ªÔÆÌåÓýThere was both a D and non-D version of the 857 and 897.857D included the audio frequency DSP that was optional on the 857. 897D got the txco and dsp. The 897 and 857 are identical circuitry in same generation. -- Leonard K. Pennock (AD7AS) On December 22, 2020 9:40:35 PM MST, Eric <eric@...> wrote:
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Re: Is FT-857D basically the same as FT-897D
¿ªÔÆÌåÓýHi Jeff, ? I¡¯m not certain but I don¡¯t believe that there ever was a non-D version of the 857. I think it was the FT-857D from when it was released, unlike the FT-100 which was the original and then they released the FT-100D which had a few enhancements such as the TCXO and larger speaker and the DSP functions. ? 73¡.Eric VK2VE ? From: [email protected] <[email protected]> On Behalf Of ka0kaf@... - ka0kaf at bellsouth.net
Sent: Wednesday, 23 December 2020 10:05 To: [email protected]; [email protected] Subject: Re: [FT-857] Is FT-857D basically the same as FT-897D ? I'm not fully sure, but I thought the D stood for digital that the D version had digital filters where the none D version did not have digital filtering. ? Perhaps someone could correct me here. ? 73 ? Jeff, KA0KAF ? On Tuesday, December 22, 2020, 05:14:46 PM EST, Richard Ferryman via groups.io <g4bbh@...> wrote: ? ? Spent today comparing TX and RX on each rig and they seem to be identical including weak signal and transmit.? Spectrum display is near identical in all modes.? Only difference is frequency stability.? Swapped the TCXOs between the rigs and found both were slightly less stable but still +/- 1Hz or so.? Think the location of the TCXO in the FT-857D is causing temperature changes when the fan runs.. |
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Re: Is FT-857D basically the same as FT-897D
I'm not fully sure, but I thought the D stood for digital that the D version had digital filters where the none D version did not have digital filtering. Perhaps someone could correct me here. 73 Jeff, KA0KAF
On Tuesday, December 22, 2020, 05:14:46 PM EST, Richard Ferryman via groups.io <g4bbh@...> wrote:
Spent today comparing TX and RX on each rig and they seem to be identical including weak signal and transmit.? Spectrum display is near identical in all modes.? Only difference is frequency stability.? Swapped the TCXOs between the rigs and found both were slightly less stable but still +/- 1Hz or so.? Think the location of the TCXO in the FT-857D is causing temperature changes when the fan runs.. Think that is enough.? The 857D was originally only purchased for my mobile operations (mostly with an ATAS aerial) and I think it was a good buy.? Richard (Dick) G4BBH. |
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Re: Is FT-857D basically the same as FT-897D
Spent today comparing TX and RX on each rig and they seem to be identical including weak signal and transmit.? Spectrum display is near identical in all modes.? Only difference is frequency stability.? Swapped the TCXOs between the rigs and found both were slightly less stable but still +/- 1Hz or so.? Think the location of the TCXO in the FT-857D is causing temperature changes when the fan runs..
Think that is enough.? The 857D was originally only purchased for my mobile operations (mostly with an ATAS aerial) and I think it was a good buy.? Richard (Dick) G4BBH. |
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Re: Is FT-857D basically the same as FT-897D
I believe that they are the same radio just in different form factors. The boards are physically different but electrically the same.
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The "little brown wire" does the same in the 857 as it does in the 897 so, if connected (or is it disconnected) it limits the power to 20W. this is useful if you're running the 857 portable off batteries as it reduces the battery drain. 73¡.Eric VK2VE -----Original Message-----
From: [email protected] <[email protected]> On Behalf Of James Clark - James_Clark at gmx.us Sent: Tuesday, 22 December 2020 06:58 To: [email protected] Subject: Re: [FT-857] Is FT-857D basically the same as FT-897D I believe they are electrical identical (do they use the same PCB?) with the sole difference being the 897 has a TCXO which the 857 does not - if yours does then it's after-market. Note: the similarity even extends to the 857 having the "little brown wire" for which it has no use but the 897 uses to detect internal battery power and thus limit output power. |
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Re: Is FT-857D basically the same as FT-897D
I believe they are electrical identical (do they use the same PCB?) with the sole difference being the 897 has a TCXO which the 857 does not - if yours does then it's after-market.
Note: the similarity even extends to the 857 having the "little brown wire" for which it has no use but the 897 uses to detect internal battery power and thus limit output power. |
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Re: Is FT-857D basically the same as FT-897D
¿ªÔÆÌåÓýI haven¡¯t done any tests, but I have both and as far as I can tell, operationally they are identical. ? 73, ? --Hank KB4MTO / TA5ZC ? ? ? From: [email protected] <[email protected]> On Behalf Of Richard Ferryman via groups.io
Sent: Monday, December 21, 2020 11:21 AM To: [email protected] Subject: [FT-857] Is FT-857D basically the same as FT-897D ? I have both and 857D and an 897D, both fitted with wide and narrow filters and TCXOs .? There are obvious differences such as size, cooling etc. but they seem to have pretty much the same specifications and I find they are funcionally the same.? I am curious to know if? the RX and TX are identical or are there differences??? I'm sure someone must have done functional tests and delved into the circuitry. |
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Is FT-857D basically the same as FT-897D
I have both and 857D and an 897D, both fitted with wide and narrow filters and TCXOs .? There are obvious differences such as size, cooling etc. but they seem to have pretty much the same specifications and I find they are funcionally the same.? I am curious to know if? the RX and TX are identical or are there differences??? I'm sure someone must have done functional tests and delved into the circuitry.
Richard (Dick) G4BBH |
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Re: Power loss
Normally the ALC increases with the drive signal to the point where the audio is over driving the power set point and then it limits the power. The ALC dropping is an indication that the drive or output is dropping due to something within the radio. If it is not SWR or over driving then it may be a problem in the driver, something loose or perhaps a filter or amp stage giving trouble,
If you have a scope that will let you take a look at the signal going to the drivers and the signal coming out you could see what is happening. Sometimes the crystal filter CF1004 could be intermittent.? I had a problem with the FET amplifier stage after the filter myself., but the power was very low and stayed low.? Do you have a problem on receive? the filters are used in both directions although in this stage not that amp. Does the power drop in other modes? FM for example? The FM and CW use a different transmit chain within the radio. I doubt it is an ALC problem from what you are telling me as it would usually increase or peg out if that was what was killing your signal. Best regards JD KE4MD |
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Re: Power loss
Willard Morton
J.D. thanks for your suggestions, ? ? My voltage is steady at 13.8 on receive and drops to 13.2 on transmit and stays steady even when the power problem occurs. ? ? The SWR remains at 0 even when the power problem occurs so no change in this value. ? ? However, the ALC drops to "0" when the power drops down to about "0".? This is the first indication of a related change noticed.? Do you have an idea what the drop in ALC means? ? ? My antenna (dipole) is in my attic so do not believe there has been any change when looking it over.? The feedline is 300 ohm twinlead which goes down directly to my Versa Tuner wire balanced connector (no balun or switch).?? I really appreciate you taking time to respond with these suggestions.? I believe that you have identified the source/cause of the power problem.? Now do you have a fix for this, or what is your recommendation?? I do not have any test equipment so if it requires any part replacement, etc, I will probably have to send it off to someone to repair it.? But at this point I believe I can point to a probable cause.?? Thanks again and very 73 Willard Morton K0BWQ
On Saturday, December 19, 2020, 07:02:36 AM CST, J.D. Barron <jeter.d.barron@...> wrote:
Check the voltage at the radio as stated above, but set your meter to read the ALC and see if that value changes and also the SWR.? In the radio the ALC voltage controls the power of the output and could possibly cut back the power if there were a problem with an incorrect signal affecting it. Of course you could have an intermittent in the transmit chain or the drivers and finals. A problem with the antenna between the tuner and the radio could also be possible as well. J.D. KE4MD |
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Re: Power loss
Check the voltage at the radio as stated above, but set your meter to read the ALC and see if that value changes and also the SWR.?
In the radio the ALC voltage controls the power of the output and could possibly cut back the power if there were a problem with an incorrect signal affecting it. Of course you could have an intermittent in the transmit chain or the drivers and finals. A problem with the antenna between the tuner and the radio could also be possible as well. J.D. KE4MD |
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Re: Power loss
Willard Morton
Phil, K4PO? Thanks for the suggestion, I haven't checked voltage but will monitor it as I transmit and see if I can learn anything.? In the meantime, I will check all connections and fuse.? I bought this radio new in 2004 so that is a possibility.? I will let you and the group know my findings. Leonard, AD7AS Yes, the cooling fan runs a lot.? But thanks for that suggestion. I appreciate the time you both have taken to respond to my problem. Thanks and 73 Willard Morton? K0BWQ
On Friday, December 18, 2020, 11:00:32 AM CST, Philip Salley <pcsalley@...> wrote:
Willard, The first thing that comes to mind is the 12VDC power reaching the radio is falling off as you transmit.? This is often caused by power line fuse corrosion or other poor connection.? The 857 is notorious for line fuse holder poor internal connections.?? Regards, Phil / K4PO |
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Re: Power loss
Is your cooling fan running ok?
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-- Leonard K. Pennock (AD7AS) On December 17, 2020 4:00:20 PM MST, k0bwq@... wrote: I am primarily a CW op and use the FT-857 as my base station.? Lately while using the 857, the power will immediately reduce down to close to zero but I can still hear myself keying..? There have been several times when I was in a CW QSO and the power dropped down to zero (about 1 or 2 w estimate), and I continued my QSO although I was told my signal had dropped some.? In my headphones, I don't notice any change in my keying.? I have checked SWR at the same time and it remains about "0".? I use the MFJ Versa Tuner and the forward power will noticeably drop down and the reflected power doesn't change (always at 0).? Then after a while it may just come back up to full power (100w) and remain for a while or go back down, and come back up or just stay down.? Then after a while, it will work ok until it drops back down, etc. |
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Power loss
I am primarily a CW op and use the FT-857 as my base station.? Lately while using the 857, the power will immediately reduce down to close to zero but I can still hear myself keying..? There have been several times when I was in a CW QSO and the power dropped down to zero (about 1 or 2 w estimate), and I continued my QSO although I was told my signal had dropped some.? In my headphones, I don't notice any change in my keying.? I have checked SWR at the same time and it remains about "0".? I use the MFJ Versa Tuner and the forward power will noticeably drop down and the reflected power doesn't change (always at 0).? Then after a while it may just come back up to full power (100w) and remain for a while or go back down, and come back up or just stay down.? Then after a while, it will work ok until it drops back down, etc.
What is going on with my unit?? Has anyone else experienced this problem? |
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Re: Removing Static (lightning) crashes
Best idea!
One RX on desired frequency and the other on near-by frequency with no signal - just static crashes! One antenna. Simply mix the audio 180 degrees out of phase. Should be "easy" with SDR RX. Desired frequency fixed, the "static crashes " RX tunes to "no signal " automatically... This? is getting too complicated... |
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Re: Removing Static (lightning) crashes
Interesting "what if" question.
It would probably work detecting "digital signal" . Say using CW and detecting start - from "off" to "on"? and then "stop" from "on" to "off" , and regenerating ( relay style)? the signal? between on / off just ignoring the mess in- between start stop. The other possibility would be "plain DSP"? what used to be called "diversity receiver"? - basically two antennas? physically separated thus receiving different signals. That would have limited frequency range... etc..etc Long time ago I had a German? WWII RX ( 1 - 10 MHz)? which had two RF preamps and allegedly? was able to do "diversity RX"? - never verified that. Of course all this is AM/CW/SSB. Will check FM during next Texas style thunderstorm - never really pay much attention how commercial FM reacts to static crashes. 73 Vaclav AA7EJ |