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Author Topic: New Yaesu SDR HF transceiver FTDX 101D due for release soon!  (Read 19983 times)
HB9PJT
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« Reply #30 on: September 19, 2018, 11:29:11 PM »

Maybe the FT-101 has two RX modes. Direct Down Converter SDR like the IC-7300/7610 and SDR with first analog mixer like the TS-890. See here: https://www.hamlife.jp/2018/09/09/hamfair2018-movie5-yaesu-ftdx101d/

73, Peter - HB9PJT
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KX2T
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« Reply #31 on: September 20, 2018, 06:18:00 AM »

Without any other specs it looks like Yaesu has a traditional front end, then a HF mixer, roofing filter then they go into the ADC's > FPGA> DSP then DAC to base band audio. The SDR section is similar to the 7300 but before the ADC's they are using a conventional front end mixer for maybe better rejection of signals but another conversion stage which may add more noise in the front end but only time will tell.
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KX2T
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« Reply #32 on: September 20, 2018, 06:36:32 AM »

Brian the 3000 does have some alc/PA bias issues, not sure if its just one stage or both but from owning one since 2013 I have seen this raise its ugly head more than a few times. Run the ALC no more than 2/3rd's of its full set scale in other words never set it to max ALC  on peaks like the manual states. If you go on line and download the service manual there is a section on setting the PA bias, make sure its on the plus side of 3 amps, that's on SSB without any modulation, also can be checked with the mic gain at zero and just use the current scale on the meter.
I did check all this out when I borrowed a buddies spectrum analyzer after getting complaints so first I verified there was issue then looked into the problem, many who never read the manual and set all gain controls to the right ending up taking 10Khz up with there SSB signal, the ALC circuit on these newer FTDX radio and that is the 1200,3000 and 5000 all have the same issues are not like the older designs in the MP series radios. The MP, MP MK5's and Fields you could almost pin the ALC without issue but these radio's also filtered the signal threw that lovely 455Khz Collins filter which was wide enough for good audio but kept the distortion products almost at bay, the ALC circuit was not as aggressive as the newer FTDX designs either. I owned allot of Yaesus for years and it had taken the 7300/7610 to break me away but you cannot make these newer Icom's get wide at all plus the phase noise in the receiver being almost state of the art makes you hear that differences between RX sections.
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W6RZ
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« Reply #33 on: September 21, 2018, 07:30:16 PM »

Maybe the FT-101 has two RX modes. Direct Down Converter SDR like the IC-7300/7610 and SDR with first analog mixer like the TS-890. See here: https://www.hamlife.jp/2018/09/09/hamfair2018-movie5-yaesu-ftdx101d/

73, Peter - HB9PJT

My guess is that the direct sampling path is just for the panadapter/waterfall display. That way, they can have a nice FFT based design with easily adjustable (and wide) width.

They do show the 9 MHz IF ADC, a Linear Technology LTC2387-18. It's an 18-bit 15 Msps device.

http://www.analog.com/en/products/ltc2387-18.html

It's an interesting choice. At 15 Msps, it would have to use undersampling to get to 9 MHz. It does have a high input voltage of 8.192 volts, so that may be why it was selected.
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KX2T
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« Reply #34 on: September 24, 2018, 09:39:42 AM »

There is simply not enough detail on the Yaesu 101, using the SDR for the scope is kind of good as far as getting things real time but if you do that you might as well use it for a host of other functions. I would like to see there reasoning on why they do down conversion then SDR, all there radio's before were down conversion roofing filtered then DSP for the last IF, some like Elecraft want you to think its like an SDR but not really, they are trying to pass DSP as a SDR stage but in reality its the last IF in those radio's which is nothing new. Maybe they have a bunch of already bought parts to build down conversion radio's and they just have to use them up, who knows. maybe they would think that a few more conversions before the SDR section would improve HF performance but I really thought that the whole reason to do SDR is to reduce the amount of stages and mixing going on to lower the noise floor and obtain excellent selectivity.
From what I had seen in the FTDX3000 and then first going to the 7300 that made a huge difference in two major area's, one was selectivity was what everyone wants which was true brick wall and two the phase noise especially for the price tag was excellent, everything else seemed to fall into place. There newer 7610 just IMO blows away a FTDX5000 I used two years ago at a buddies house so this FTDX101 has to be better than the 7610 to start at $4.5K price tag and better top the charts over the Flex 6700 and K3S. You also have the new Kenwood TS890 that may be the K3s killer but for what another over $4k radio with no second RX. I must say that you have to give Icom the the hand here, first to market from the big three in SDR and setting the pace for many who try and follow plus I really don't think they are done yet, there soon may be another radio coming out from Icom that will be another heavy hitter like there statement IC7851 was for one of the best none SDR radio's but the next radio will be SDR and take it to the limit. I really don't think Kenwood is entrenched into the amateur market that much and Yaesu now going back to its roots without the large corporate giant Motorola funding there R&D so they are not in the position they were 10 years back.
Time will tell and hopefully October we will see but the Kenwood is already out in England but nothing about FCC approval yet, N/A on the Yaesu yet.
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