Tecsun Pl-990x And Pl-680 Sync/Zerobeat Test 

You're welcome Phil, yes beautiful place and it would be much better if we had as much Blue skies as dark cloudy skies lol. I haven't made it Down Under yet, hopefully someday.

Recomenda o PL 680 ?

@@sidneycavalcant Yes, absolutely PL-680 is one of the best new radios you can buy today, while some of the DSP radios might be a little bit more sensitive they can not use ECSS because the quality on SSB is so poor so yes, PL-680 in my opinion is one of the best radios you can get. I will never buy a DSP radio again. Sim, absolutamente PL-680 é um dos melhores novos rádios que você pode comprar hoje, enquanto alguns dos rádios DSP podem ser um pouco mais sensíveis, eles não podem usar ECSS porque a qualidade em SSB é muito ruim, então sim, PL-680 na minha opinião é um dos melhores rádios que você pode obter. Nunca mais compro um rádio DSP.

Congrats on your purchase of PL-680, it's one fine radio especially for ECSS, it sounds so good compared to a DSP radio. The PL-680 and good external antenna and the 680 is one of the best radios you can buy new today. I sold my 990x mainly to fund other radios manly the H501x and couldn't really tolerate the SSB problems for the cost of the radio. I then got the H501x and while it's filters work better, the sound is better but the distortion remains and I now consider selling the H501x.

@@o00scorpion00o Thank you sir. ☺📻 I forgot to add that my PL-680 came with the firmware 6622, the exact version as my PL-660. Now that came as a surprise to me, since I had thought that every Tecsun model has its own firmware! I was expecting to see "68xx" but instead it showed "6622". If both models share the same firmware then their differences lie in the speakers fitted and perhaps the audio circuitry, not to mention the outer body shell and buttons. That said the 680 does sound more bassy than the 660. The reduction in the higher frequencies does help reduce the HF background noise. VHF Air band quality is about the same as the PL-660, no discernible difference . I don't mean any disrespect but I think you're the only SW reviewer on RU-vid who mentions ECSS quite a lot! ☺ I learned something about sideband AM listening from your channel. ECSS is a good thing to have but the reality is that in 2023 the shortwave band is not as overcrowded as it was like in the 1980s and 90s. At least not in my part of the world. 😎 I've tried ECSS on shortwave but the sound quality isn't as good as regular AM. The same goes for Sync Detection. SD was a feature which I used quite frequently with my old Sony ICF-7600G back in 1999, but Tecsun's Sync Detection is nowhere as good as Sony's, especially their iconic ICF-2010D. Personally I don't chase down HF utility signals with my PL-990 (I hope to do that with the RTL-SDR Blog V3 that I've just ordered), therefore I don't take much stock into the PL-990's filtering quality. For the relatively low price I paid for it, I don't expect it to be even a poor man's Yaesu FTDX-10. 📻👍 Today's shortwave wasteland has even led to CGTN Radio and China Radio International experimenting with transmissions as wide as 15 kHz and they're impossible to miss even with casual band scanning. I'm not sure if the ITU has given both Chinese stations its blessings but AFAIK, shortwave stations are supposed to adhere to the 5 kHz bandwidth frequency spacing rule. You could say that CRI and CGTN's transmission quality is almost like MW broadcast and the only thing they haven't tried is broadcasting in stereo, lol. 😂 As for the PL-990, I think Tecsun took the shortcut by relying the DSP chip for its AM bandwidth filters rather than adding a dedicated analog filtering circuitry. The VFO is however, is of an analogue PLL synthesis design. I don't know much about the cost of designing and implementing analogue bandpass filtering but I think it could be costly. The Silicon Labs Si4735 chip offers a total of 7 digital bandpass filters and XHDATA's D-808 is the only receiver that makes use of all of them. I can imagine if the XHDATA manufacturer designed the D-808 with seven analogue bandpass filters they can't sell this radio for the cheap price it commands. Hope you'll find something better than the H-501x though. 😎🙏

@@StratmanII I welcome other opinions so I'm not easily offended 😀 ECSS, well you can look at it's uses in a couple of ways, yes, sound quality reduces because you're basically cutting out half the bandwidth., but, and I'll try explain below, it can actually sound better than a DSP radio using it's narrower filters. Some stations can indeed be quite close together, I find the shortwave bands quite busy day and night depending on bands, you know the usual bands busier in the day and others at night, but I often find that ECSS improves my listening experience. If I'm listening to a station and there's another station close by or interfering noise, I've often found that the filtering on a DSP radio isn't good enough to filter it out, you're narrowing the filter on both side bands and if you go narrow enough it can sound a lot worse than simply cutting one of the sidebands using USB/LSB it can acutally sound better than just using a narrow DSP filter be it on a DSP radio or SDR. I often find that using SYNC on my Kiwi SDR for example sounds much better than just narrowing both sidebands, SAM is good against fading on the Kiwi and "SAL" for lower sideband and "SAU" for upper sideband. In other words, with just tighter filters you can end up with a narrower bandwidth than using USB/LSB to get the same effect which can make ECSS if you want to call it sound better than just relying on filtering alone. Regarding the firmware, I have no idea what version my 680 uses, my 660 was quite old and suffered more from internal muting on weak signals that the 680 doesn't, the 680 has more bass alright. The fact the 660 and 680 have the same firmware for your radios can mean anything with Tecsun. 😃 A PL-660 today might operate quite different to my old one if they're actually still producing them new. I would still not tolerate such bad sound quality on SSB given the cost of the PL-880, 990x, S-8800 and more recent the 330 and H501x, the 330 I can forgive due to it's cost and size, it probably wouldn't have been possible to make a radio so compact using discreet components. The Belka DX sounds good, I like it, remarkably compact but have to say I hardly use it, I love using the PL-680 far more. I have the original Russian Malahit DSP 2 and it's a really great radio, it needs an external antenna though but it's an excellent radio. One of the really great things I find with the PL-680 is it's low noise floor, the Sangean ATS 909 X2 is also another great radio with a low noise floor. Check out my Kiwi SDR if I haven't shared the link already here it is emeraldsdr1.ddns.net:8074/ It's using a 40 meter long End Fed Half Wave 49:1. Now I'm just waiting for someone to make a radio like the Malahit DSP 2 ( now DSP 3 ) in a larger box with more buttons and knobs, I don't like the way these radios are so tiny.

Thanks for watching. Remember the 4 kHz filter doesn’t work on the 990x, it didn’t work on the 880 or S-8800 either. The 990 is a good radio but on ssb even the cheap Degen DE-1103 is better. But for the serious SW DX’R the PL-680 is one of the best portables out there. I wish Tecsun concentrated more on the receiver than adding Bluetooth and SD card playback for their last flagship portable, it’s sad really as it should have been so much better. I’ll probably sell the 990x in the new year, and hope that the new Sangean 909x2 is better than the old 909x, nice radio but the audio on AM isn’t good and while SSB audio is a lot better than the Tecsun the audio out level via headphones is far too low and Zerobeat on am isn’t fantastic due to the 100hz only tuning so hopefully the 909x2 is better it does worry me when I read that it has automatic bandwidth, I want to be the one to choose and the old 909x filter was not good either.

@@o00scorpion00o Fully agree with you about the 4.0 kHz DSP filter. I owned and resold two S-8800s, and came to the conclusion this model is poor to listen to on SSB or ECSS. Have you tried the BELKA-DX? Now this is a radio that is superb on SSB even though though the filters are DSP. Each bandwidth sounds distinct, too, with decent shape factors. I am waiting for the speaker-back option for mine to arrive.

@@4nradio782 Yes I have seen the Belka but wanted a real radio with decent audio that LW/MW works with external antenna. I love the Sony ICF-2001D but wanted something more modern. Even though I mostly listen via headphones I'd like something with decent audio for when I don't want to listen with headphones. I might look into the Sony ICF-77 too because I think they look great, that's if I can find one at a decent price in good shape.

@@o00scorpion00o do i detect a little sarcasm concerning the belka dx? Have you had the belka and reviewed it? "ALL" the reviews I've read about it have been 5 star. If you only listen to LW and MW I can understand, but I'm buying it for shortwave. On a side note the 680 sucks on MW compared to many others.

@@carlboches4090 No Sarcasm at all, reading back I can see where someone might think I was being a little sarcastic. What I meant by "real radio" which was a poor choice of words but what I meant is a traditional radio with knobs and buttons that has decent audio from it's speaker that works well with external antenna on LW/MW. The belka DX doesn't meet that criteria of traditional radio and that's all I meant. I just looked it up and sadly and surprisingly there is no Longwave and most of Medium Wave is missing, that seems rather odd but I'm not entirely sure I'd spend so much when I really want Longwave, I'd have to think about that. I would like to test it out but I'm just thinking if someone went to the trouble why omit LW/MW ?

Thanks for watching, yes the PL-990x, 880, S-8800 sound is atrocious on SSB, the PL-330 is better and the H501x but far from perfect. I will never again buy a DSP radio unless SSB sound quality has been resolved which is unlikely.

Sorry pal, I missed this post, the XHDATA is a great radio for the money just doesn't work well with external antenna and still has some distortion on SSB and it's not easy tune on SSB. But for the money I can't complain much, it's great to just put in your pocket while on the move.

@@o00scorpion00o no problemo. im having tons of fun with the 310et. that will be my super duper ultra portable. it really is sensitive. in any case, the 680 should be in my collection next year or so. be safe and best 73s.

@@DXPedro My 310 ET is still going strong it would have been great if it had SSB but I do like ETM it's very convenient.

@@o00scorpion00o yes it is! i recently made a video on how to improve ETM sensitivity on the 310et. i would be ok if it had ssb or a full SW spectrum. either way, loving it every second.

i saw you commented on my video, but then the comment disappeared ? xD

Thanks for watching! Yes, there's always more to learn, great hobby!

Hi and thanks for watching. Yes, indeed you are correct. I did figure it out quickly but it makes little difference, the audio is so poor on SSB I sold the radio, I just have to have good audio quality on SSB. I have the PL-330 and I can forgive it for the money having some issues but a big surprise was how well the little 330 handles external antennas especially at night. This was a huge surprise. It does have it's limitations because there's no antenna attenuator, this would have made an even bigger difference, however, one very strong Longwave station here in Ireland is to close on the 14th April and this has caused a lot of receiver overloading for me even on my kiwi sdr radio so I had to build a wave trap to reduce 252 Khz by several Db and only 252 Khz and it worked perfectly, so once this 252 Khz is gone I will have much less overload issues on my radios. Sad to see another AM station go in Europe. Anyway, the SYNC on the PL-330 is not fantastic either but the big difference to both the PL-330 and the H501x is that the 4 Khz filter now works on SSB and Filter performance has improved in general so even 3 Khz sounds much better than on the 880,990x and S8800 but sadly there is still some distortion but it doesn't appear as bad as on the 880,990x and S-8800 but it should not be there. There's no DSP radio that can beat the PL-660/680 for pure audio quality on SSB which makes the PL-660/680 fantastic Shortwave DX chasing radios. The filters are a bit wide for Ham radio on a busy band but for SW DX the 660/680 are far better using ECSS and SYNC than any DSP radio I have ever heard. DSP might make for good marketing and might make component count less which makes cheaper radios but there should have been more analogue radio improvements or just go with SDR.

FM reception on the 680 ? hmm not sure I noticed it was bad, it picks up everything my other radios pick up but to be honest I don't use it much on FM but might be worth testing it against the 990x.

@@o00scorpion00o I guess I shall make a video comparison with few other radios on FM.

It depends on what you might call an improvement, SSB sound quality is rubbish on the PL-880 and you really won't believe how good it is on the Pl-680 until you hear it for real then you will sell the Pl-880. In fairness to the Pl-880, 990x they are decent radios on FM, LW, MW and SWL, But SSB lets them down badly. The Pl-880 is more sensitive on the whip than the PL-680 but if using some extra wire hooked up to the antenna it's a non issue, I mostly use external antenna, the Bonito MA-305 is a superb receiving antenna and matches the portable radios very well without much overload, on the Pl-680 and Bonito MA-305 if I detect some overload I change the antenna to local or medium position and that cures any overload but depending on your area with big AM or SW transmitters close by you might still have some issues, I really can't say but for me it's not an issue on the 680, as I said, with use of the Attenuator switch on the radio it usually fixes any minor overload, for me. 150 feet of wire provides a lot of signal for portable antennas not necessarily giving any benefit over the likes of the Bonito MA-305 which is optimised for receiving with low noise, some wire antennas can pick up a lot more noise, the Bonito is an excellent DX antenna and your wire might be better for NVIS ham radio. So back to the PL-680, if you like chasing DX you can use USB/LSB to reduce or eliminate interference or if there is a station close by effecting the DX station you want to hear, switch to USB/LSB whichever has the best effect and tune the BFO until the audio sounds as natural as possible, you can't do this with the PL-880 or Pl-990x or even the S-8800 because SSB sounds so bad. So the Pl-680 is really a DX champ, especially for the money.

@@o00scorpion00o thanks I think I will buy the 680 and if I see what I like then I sell 880 or keep them all. You can’t have too many radios lol

@@bigkamran True, you can't have too many radios lol, but the XYL's don't understand this lol :-) If you get the 680 let me know what you think of it, I think you'll be amazed with the audio on SSB.

@@o00scorpion00o I placed the order with Anon-co and should be getting it this Friday, can't wait to run it against the 880

@@bigkamran Did you get the PL-680 after and what do you think of it on SSB compared to the 880 ?

Hi and thanks for watching, the station is killing you, what do you mean ?

@@o00scorpion00o The content of station you were tuned into, I have a problem with people yelling God at me. Not about you, you were just demonstrating the aspects of the radio.

@@mosfet500 oh right, to be honest I wasn’t paying much attention to the programming 😊

Thank you! I’m saved!

@@user-fu8vn7xo6c Wonderful! thanks for watching !

I don’t think so at least on battery, haven’t tried with the AC adapter.

It depends on the signal strength/antenna being used, day/night etc. Whatever the antenna position, it won't change the distorted and poor audio quality of the 990x or the PL-880 or the S-2000, if they got the DSP chip, the XHDADA-D808 is the same, I have not yet head a DSP radio that did not suffer from this distorted audio on SSB. The PL-330 and the H501x do reduce the distortion but the big difference between the 330/h501x is that the filters are different and the audio sounds a lot less muddy + they are the first Tecsun radios where the 4 Khz filter actually works. The downside of the 330/h501 is that there is a big low frequency cut off which can make the audio very thin sounding, but, the 330 and 501 do sound better on SSB but, the distortion is still there, it might be reduced but it's still there. I have not yet heard a good sounding DSP radio on SSB and I would never tell anyone if they listen to SSB or like to use ECSS to get a DSP radio, I would tell them to get a PL-680 or any older analogue radio or if they want a modern receiver to get a Malahit DSP 3, original Russian design, that's a really geat radio and I hope someday someone makes a SDR radio like the Malahit in a traditional radio box with knobs and buttons. It would have been best if Tecsun just released an improved analogue design for the H501x due to it's size, the 330 probably benefits from DSP to make it so small and because it's so cheap I could forgive some imperfections, however, that muting when tuning would drive me insane if I had to use it long term.

SSB uses half the bandwidth, Sync can in theory sound better because it uses more bandwidth, the SYNC on some radios is better on others and sometimes using SSB can be better at reducing the effects of fading.

The PL-880, 990x and S-8800 don't have SYNC in the traditional sense, those radios just seem to rely on SSB and when you enable SSB you get poor sound and distortion particularly on strong stations but the sound quality on SYNC on the PL-680 is far better than on the dsp radios + if you use SSB on the PL-680 you can really pull out very weak signals out of closer stronger stations, this is almost impossible on the PL-880, 990x and S-8800 because they sound so bad, the audio on the PL-680 is vastly better. I had the S-8800 and sold it because of this distortion on SSB. So use USB, LSB on the 660 again on a SW commercial station and tune the BFO until it sounds as natural as possible, it's leaps and bounds better than the S-8800, 880, 990.

The 680 Sync is good but using USB, LSB is much better, tune the BFO until the sound is as natural as possible. try it, ECSS is what that is called for those unaware.

Sorry, what SYNC are you referring to ?, it would help if you'd be more specific, what did I say didn't work ?

Hi and thanks for watching, do you mean the medium wave band or the mode AM ?

Am

​@@eyadabusharar2457 This is a hard one for me to explain what I think and the reasons why in a shortish reply but I'll give it a go. If you listen to SSB the the PL-680 is the best, by far as the audio quality on the 990x is truly rubbish as it is with most DSP radios which is the No.1 reason I avoid them. Even if you don't listen to SSB and listen to Medium Wave and Short Wave bands using SSB has huge advantages to reduce the effects of fading and sources of noise that the filters on DSP radios often can't remove because the noise is still within the passband of the filters where as using SSB eliminates one side of the carrier altogether and this method is called ECSS. The advantage the PL-990x and H501x + the PL-330 is that LW and MW reception is greatly improved when using an external antenna, unfortunately this is not the case with the majority of radios including the PL-680. On the PL-990x you have to press and hold No.5 until CH-5 or something like that appears on the screen, this disconnects the internal antenna, if you don't do this then the radio will overload. If you listen mainly to the Shortwave bands than I would get the PL-680 because the radio is a lot cheaper and performs excellently with external antenna, I always recommend an external antenna if you can get the Bonito MA305 with optional longer whip it's a tiny antenna with remarkable performance. If however you want to only use the telescopic whip antenna then the PL-990x has slightly better performance but you might find that with all the electrical noise from modern electronics that you can't pick up much more than noise and will have to head out of town in the country. In a noisy environment an External antenna might not work too well either but it will always work a lot better than inside. You can see if sources of noise are coming from your home, LED light bulbs, phone and laptop chargers especially non original imported junk can cause a lot of noise. I hope I explained the difference between the 2 radios ok ? 🙂

What a nice informtion Thanks a lot 😊

Correct, it's not, I got caught up making the video and didn't realise my mistake. SYNC on these DSP radios is rubbish and it doesn't work. SYNC on the PL-660 and 680 is vastly better sounding and performs better but for ultimate selectivity using USB/LSB always works better than using DSP radio with narrower filters because the analogue radio sounds vastly superior on SSB and this is crucial for the serious DX-er or to greatly reduce or eliminate the ever increasing amount of interference on Shortwave. + on SSB the analogue radios have a much lower noise floor than DSP radios.

zerobeat, ECSS all the one really, basically Zero beat is when you are on an AM station and turn to USB/LSB and tune the BFO until there is no tone, until the audio is as natural as possible, this works brilliantly on the ATS-909 x2 and Pl-680 but unfortunately it does not work on the Pl-880, 990x and S-8800 and probably all DSP radios because the audio quality on SSB is very poor.

@@o00scorpion00o no 330 funciona ?