Re: [digitalradio] RFSM8000 and Yaesu FT857
On Saturday 19 April 2008 12:19:55 am Leskep wrote: Hi Alan This is using the digi port on the 857 with all dsp functions off but I need 2400 hz of audio passband just to fit the non standard RFSM8000 signal in and just cant get it from stock standard 857 Maybe just put it back in my mobile and consider other options for digital use - at least the FT920 works well on RFSM Regards Les I had one of these and it was typical for me to get 2700 hz bandpass from it. Did it all the time. Are you sure the DSP is off? It sounds like the audio DSP is on and set wrong. Even if it's on, you can set the lower and upper cutoffs to min and max settings. Then you can use the IF shift to move the passband left and right in the IF stages. Perhaps the IF shift is not centered. There are three buttons to the left of the display. Hold the middle on in for more than two seconds. That is the IF shift. To start off, it needs to be centered. Move the selector knob (lower left) to get a large dot on the right hand of the freq display. If you are away from the IF center, you will get an up or a down arrow instead of a large dot. Once you get a large dot, hold it in another two seconds to set it. Then select the two submenu items for DSP lower limit and set it to as low as it will go. Do the same for the DSP upper limit and set it to as high as it will go. You should get about 3 khz bandwidth. -- In order to ensure a safe police state; the right of the people to keep and bear arms must be infringed.
Re: [digitalradio] RFSM8000 and Yaesu FT857
Les, According to the RFSM web page, you need at *least* 300 to 3000 Hz audio response, and preferably 300 to 3400 Hz. Even an INRAD filter is not going to completely meet the 3000 Hz high end requirement, much less a 3400 Hz requirement. I think some other Yaesu rigs optionally support a 3300 Hz high end with an optional Yaesu filter, but my point was that if your low end is only 700 Hz, something is misaligned on your FT-857 to start with. You also could wind up paying for an INRAD filter and still find the low end or high end inadequate because the audio itself is rolled off too fast. Anyway, it is probably better to use something other than the FT-857 for digital modes as finding the ALC threshold is very critical for getting low IMD, even on PSK31, and drift is a problem on 2 meters unless you have the TCXO option, which my FT-857 does not. 73, Skip KH6TY - Original Message - From: Leskep To: digitalradio@yahoogroups.com Sent: Saturday, April 19, 2008 12:11 AM Subject: Re: [digitalradio] RFSM8000 and Yaesu FT857 Hi Skip The problem is that I need to pass around 2.4 khz of signal audio and with the stock filter it will not do it - have to look at a wider filter or an IC7000 hihi Regards Les From: kh6ty Sent: Saturday, April 19, 2008 11:40 AM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] RFSM8000 and Yaesu FT857 Les, Are you sure it is the IF passband? If your BFO injection frequency is set correctly, you should be able to pass 300 to maybe 2200 Hz. Otherwise, SSB phone will have no lows. If you have audio transformers in a homebrew interface, make sure they have the necessary frequency response. The best around here seem to be the little green ones from Radio Shack. 73, Skip KH6TY - Original Message - From: Leskep To: Digitalradio Sent: Friday, April 18, 2008 9:08 PM Subject: [digitalradio] RFSM8000 and Yaesu FT857 Greetings to all Is anyone using the FT857 for RFSM8000 I have been trying mine out over the past two days after getting a new Signalink USB interface Big problem with the RX passband - it is not wide enough using the standard filter supplied with the FT857 and consequently too much of the signal is cut off on the low frequency end of the audio Waterfall shows that there is no or very little audio up to about 700 hz making it impossible so far to make a connect even though it will spring up the called station every time Any ideas? I am now looking at an INRAD filter either 2500 or 2900 that would allow the required passband audio Any comments or feedback welcome Regards Les VK2DSG No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.1/1385 - Release Date: 4/18/2008 9:30 AM -- No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.1/1385 - Release Date: 4/18/2008 9:30 AM
Re: [digitalradio] RFSM8000 and Yaesu FT857
Les, Are you sure it is the IF passband? If your BFO injection frequency is set correctly, you should be able to pass 300 to maybe 2200 Hz. Otherwise, SSB phone will have no lows. If you have audio transformers in a homebrew interface, make sure they have the necessary frequency response. The best around here seem to be the little green ones from Radio Shack. 73, Skip KH6TY - Original Message - From: Leskep To: Digitalradio Sent: Friday, April 18, 2008 9:08 PM Subject: [digitalradio] RFSM8000 and Yaesu FT857 Greetings to all Is anyone using the FT857 for RFSM8000 I have been trying mine out over the past two days after getting a new Signalink USB interface Big problem with the RX passband - it is not wide enough using the standard filter supplied with the FT857 and consequently too much of the signal is cut off on the low frequency end of the audio Waterfall shows that there is no or very little audio up to about 700 hz making it impossible so far to make a connect even though it will spring up the called station every time Any ideas? I am now looking at an INRAD filter either 2500 or 2900 that would allow the required passband audio Any comments or feedback welcome Regards Les VK2DSG -- No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.1/1385 - Release Date: 4/18/2008 9:30 AM
Re: [digitalradio] RFSM8000 and Yaesu FT857
Hello, You should be using the digi port, and there is a specific setting that allows you to center the filter passband around typical digi signals. I find 200 hz up works best for ALE. Since the signal is now centered, I can then even use the DSP bandpass to really tighten up. If you have not centered the signal, or are using USB you will need to turn DSP bandpass off. I don't know how the signalink interfaces, but the 857/897 needs no interface for soundcard/tnc usage and is already decoupled at the digi-port on the back of the radio. Have fun, Alan km4ba
Re: [digitalradio] RFSM8000 and Yaesu FT857
Hi Skip The problem is that I need to pass around 2.4 khz of signal audio and with the stock filter it will not do it - have to look at a wider filter or an IC7000 hihi Regards Les From: kh6ty Sent: Saturday, April 19, 2008 11:40 AM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] RFSM8000 and Yaesu FT857 Les, Are you sure it is the IF passband? If your BFO injection frequency is set correctly, you should be able to pass 300 to maybe 2200 Hz. Otherwise, SSB phone will have no lows. If you have audio transformers in a homebrew interface, make sure they have the necessary frequency response. The best around here seem to be the little green ones from Radio Shack. 73, Skip KH6TY - Original Message - From: Leskep To: Digitalradio Sent: Friday, April 18, 2008 9:08 PM Subject: [digitalradio] RFSM8000 and Yaesu FT857 Greetings to all Is anyone using the FT857 for RFSM8000 I have been trying mine out over the past two days after getting a new Signalink USB interface Big problem with the RX passband - it is not wide enough using the standard filter supplied with the FT857 and consequently too much of the signal is cut off on the low frequency end of the audio Waterfall shows that there is no or very little audio up to about 700 hz making it impossible so far to make a connect even though it will spring up the called station every time Any ideas? I am now looking at an INRAD filter either 2500 or 2900 that would allow the required passband audio Any comments or feedback welcome Regards Les VK2DSG -- No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.1/1385 - Release Date: 4/18/2008 9:30 AM
Re: [digitalradio] RFSM8000 and Yaesu FT857
Hi Alan This is using the digi port on the 857 with all dsp functions off but I need 2400 hz of audio passband just to fit the non standard RFSM8000 signal in and just cant get it from stock standard 857 Maybe just put it back in my mobile and consider other options for digital use - at least the FT920 works well on RFSM Regards Les From: Alan Barrow Sent: Saturday, April 19, 2008 1:55 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] RFSM8000 and Yaesu FT857 Hello, You should be using the digi port, and there is a specific setting that allows you to center the filter passband around typical digi signals. I find 200 hz up works best for ALE. Since the signal is now centered, I can then even use the DSP bandpass to really tighten up. If you have not centered the signal, or are using USB you will need to turn DSP bandpass off. I don't know how the signalink interfaces, but the 857/897 needs no interface for soundcard/tnc usage and is already decoupled at the digi-port on the back of the radio. Have fun, Alan km4ba
