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Saturday, March 23, 2019

Japanese Broadcasters Association calls for a system revision to abolish their AM broadcast services

This is news from KYODO(in Japanese). 

   According to a news interview to the officials on March 22nd, the Japanese private broadcasters decided to request the Ministry of Internal Affairs and Communications to revise the system reform to abolish AM radio broadcast and make it possible to convert it to FM broadcast. A representative from the Japan Commercial Broadcasters Association(JAB) will make a statement at the ministry's expert conference held on March 27th.

    Most of the AM broadcasters want to unify their broadcasts into the supplementary broadcasts (wide FM)  that is carried out as a disaster countermeasure in response to the stagnant advertising revenue from AM broadcasts. If the system reform is realized, there is a possibility that private AM broadcasts will be abolished in the future except for some areas such as Hokkaido.

    According to officials, JAB calls for a system revision by 2028 so that it can be converted from AM to FM.
(Note: I translated KYODO News on March 22nd written in Japanese to English.)

Friday, March 22, 2019

Taitosaki MW DX-pedition in spring

 春の太東崎MW DXペディション   

    I enjoyed MW DX-pedtion with my friends of TDXC at Taitosaki on the seaward side of Chiba prefecture on March 21. The MW condition was not good. I checked the SDR data roughly after I came home and I could hear these regular MW stations of the U.S. as follows.  There were a lot of carriers on 10-kHz separation but the signal levels were weak. I wish the station on 1220kHz was KQMG.


My Log is as follows. Time is Japan Standard Time (UTC+9hours) 

567   KGUM          18:59:55 "K-57 KGUM Agana Guam"
630   4QN             Non-ID but continuous program in Australian English. 
630   KUAM        18:02:02 "Isra 63" 
680   KNBR           18:00:05 "KNBR" 
710   NBD("HY")  
780   KNOM          18:59:56" KNOM.. 2a.m."
801   KTWG          19:01:13" KTWG AM800"
850   KICY            Russian language and music
980   CKNW          17:59:56 "..entertainment station .. at"
1010 CBR             18:00:00 "CBC News.."
1040 CKST           18:01:52  "TSN10-40 iHeartRadio station" 
1070 CFAX           18:00:04  "C-FAX"
1100 KFAX           18:59:54 "KFAX San Francisco"
1110 KFAB           18:00:14 "11-10 KFAB.."
1120 KPNW          18:00:00 "KPNW Eugine"
1130 CKWX          19:00:00 "CKWX"
1160 KSL             18:00:00  "KSL"
1220 KTMG or KQMG 19:00:00 very weak.
1310 KMKY          18:50:00 "KMKY AM 13-10 Oakland San Francisco"
1310 KXIL            18:00:00 ".... Idaho"    
1320 CHMB          18:00:00 "This is CHMB AM 13-20"
1380 KRKO          18:59:23 ”KRKO Everrt”
1410 CFTE           17:59:52 "CFTE AM Vancouver iHeartRadio"    
1420 KKEA          19:00:04 "KKEA Honolulu"
1470 CJVB           17:59:50 "CJVB"
1480 KGOE          18:00:01 "KGOE"
1500 KHKA          19:00:00 "News radio KHKA Honolulu"
1540 KREA          18:00:00 "This KREA Honolulu 15-40"
1540 KMPC          18:00:00 "Radio Korea KM..15-40"
1550 KRPI           18:00:00 "You're listening to 15-50 AM KRPI.."
1600 KVRI           19:00:04 "KVRI"

  We were mainly digging MW TP-DX stations in grey line zone time(from around 18:00 to 19:00 J.S.T.)

Grey line zone time started from around 18:00 J.S.T.

Saturday, March 2, 2019

Real time grey line watching by a Night'n Day Real Solar Time Rotating Globe by Fabien Vienne


  I ordered a second-hand  Night'n Day Real Solar Time Rotating Globe made by Fabien Vienne at a very low price.  This globe has already been discontinued. This globe shows us moving night and day area on the globe by an electric ramp.  I would like to watch the moving night area including grey lines that is an important factor for low band radio wave propagation including MW band.


  The seller doesn't ship this item to Japan, but I use the address service of Shipto that gives me the shipping address in the U.S. for the delivery. After the item is delivered to the address in the U.S., this company ships the item to me in Japan by paying the reasonable shipping cost.   


  During watching the globe, I want to listen to this nice song ”Night and Day" by Diana Krall.
  この地球儀を眺めている時には、ダイアナ・クラールの”Night and Day"を聞きたいですね。

Sunday, February 24, 2019

Comparison of RADIWOW R-108 and TECSUN PL-380

Сравнение RADIWOW R-108 и TECSUN PL380

   I conducted a comparison of RADIWOW R-108 and PL-380 in terms of RSSI and SN ratio of both receivers. My test results are as follows. If I were allowed to criticise  RADIWOW R-108, I would say RADIWOW R-180 is still a developing receiver, but it is close to completeness. 

  Я провел сравнение RADIWOW R-108 и PL-380 с точки зрения соотношения RSSI и SN обоих приемников. Мой вывод таков. Если бы мне разрешили критиковать RADIWOW R-108, я бы сказал, что RADIWOW R-180 все еще находится в стадии разработки. (by Google translation for Russian friends)

 RADIWOW R-108とTECSUNのPL-380の受信性能を比較してみました。結果は以下に示すとおりですが、もし、RADIWOW R-108を私が評価してもいいのなら、R-108はまだ発展途上のラジオだと言いたいです。マイナーな問題が解決できればいいラジオになると思うのですが。

I heard that there are still some individual differences among RADIWOW R-108s. This test was conducted on only my purchased receivers.

注意:今回の評価は、あくまでも私が購入したラジオによるものです。RADIWOW R-108には個体差があるように聞いています。

1. General feature

  RADIWOW R-108 is smaller than TECSUN PL-380, and I like RADIWOW R-108 has a small tuning dial at the right side of the receiver. Tuning feeling is much better than that of TECSUN PL-380.  I prefer the external antenna input employed to RADIWOW R-108 too. Two anti-slip rubber at the bottom of RADIWOW R-108 is excellent.  I also want to tell you that RADIWOW R-108 can receive AIR band.

RADIWOW R-108は、TECSUN PL-380よりも小型です。RADIWOW R-108のチューニングダイヤルはいいですね。チューニングフィーリングも良く、TECSUN PL-380より快適にダイヤルチューニングできます。またR-108には外部アンテナ入力が付いているのもいいですね。R-108の底についているゴムの滑り止めもなかなか良いです。R-108にはAIRバンド受信機能も付いています。

Photo 1. RADIWOW R-108  and TECSUN PL-380

Photo 2. Side panel and bottom of RADIWOW R-108
You can see the external ANT input.

2. FM Reception

  Both receivers work well, and I don't feel any significant difference between them. Even though the audio at the high-frequency range above around 10kHz of TECSUN PL-380 is slightly better than that of RADIWOW R-108, the sound from the speaker of RADIWOW R-108 is easy to listen. You can choose RADIWOW R-108 as your companion of FM reception during your trips.
どちらの受信機も良く受信します。特に大きな違いは無いように感じます。TECSUN PL-380の音の方が、10kHz程から上のオーディオレンジで、RADIWOW R-108より若干良くなっていますが、スピーカーから出る音は、RADIWOW R-108のほうが聞きやすいです。旅行先でのFM局の受信にRADIWOW R-108を使うのは「あり」だと思います。

   The comparison of pink-noise sounds between RADIWOW R-108 and TECSUN PL-380 (The 6-second audio from the beginning is from RADIWOW R-108 and the latter is from TECSUN PL-380. You can notice that TECSUN PL-308 has better high-audio range than RADIWOW R-108. )

FMのピンクノイズを両者で比較してみました。前半6秒がRADIWOW R-108、後半6秒がTECSUN PL-380の音です。前述したとおり、PL-380のほうが、若干高域が向上しているのがわかります。

If you cannot play this audio this is due to google drive policy. Please try it after several days.


Photo 3. FM reception test at my balcony
(I set each receiver independently.)

Figure 1. Comparison of RSSI of received FM radio stations
(The maximum value in about 20-seconds observation)

Figure 1. Comparison of SN ratio of received FM radio stations
(The maximum value in about 20-seconds observation)
Photo 4. FM reception test in my room
(I set each receiver independently.)

Figure 3. Comparison of RSSI of received FM radio stations
(The maximum value in about 20-seconds observation)

Figure 4. Comparison of SN ratio of received FM radio stations
(The maximum value in about 20-seconds observation)

3. SW Reception

  Unfortunately, I didn't have enough time to catch many SW radio stations. But I felt something unstable sensitivity of RADIWOW R-108 among SW bands. In terms of SW radio stations that I caught to do the comparison of both receivers, The RSSI of TECSUN PL-380 was always better than that of RADIWOW R-108. When any button is pushed buzz noise occurs during SW reception.
  In terms of speaker sound, the intelligibility of TECSUN R-380 is much better than that of RADIWOW R-108, but the sound of RADIWOW R-108 is better for a long time listening.  If you want to dabble a RADIWOW R-108 for SW listening during your trip, it will be a good choice, but I don't recommend you to use the RADIWOW R-108 for serious SW DXing.

残念ながら、十分な時間がなかっため、沢山の短波放送局を受信することができませんでしたが、感度については、RADIWOW R-108に不安定さを感じました(BAND間で違いがあるように感じました。※15.0MHzのBPM受信)また今回受信による比較では、TECSUN PL-380の方が受信電圧は常に高い状態でした。さらに短波受信中に何かボタンを押すと、ブブブと雑音が出ます。スピーカー音の比較では、了解度はTECSUN PL-380が上ですが、長い時間のリスニングには、RADIWOW R-108の方が良いように思います。もし、旅行先でちょっと短波受信にRADIWOW R-108を使ってみる分には、R-108はいい選択肢になると思いますが、まじめにSW DXingするためのものとしてはお勧めはしません。

  I conducted a test by setting each receiver independently at my 7th-floor balcony. I only used each whip antenna for this test.
Figure 5. Comparison of RSSI of received SW radio stations
(The maximum value in about 20-seconds observation)

Figure 6. Comparison of SN ratio of received SW radio stations
(The maximum value in about 20-seconds observation)
The SN ratio indication of SW reception seems to be up to 25 dB.

4. MW Reception
  Both receivers work well to listen to "local" MW radio stations. There is a significant difference between them in terms of RSSI and SN ratio. However, in terms of receiving weak MW signals with fading, the sound level change of RADIWOW R-108 is very natural compared to TECSUN PL-380. I felt the sound of TECSUN PL-380 for that case is bouncing and fluttering. I don't like the fluttering sound. 
You can choose RADIWOW R-108 as your companion of MW reception during your trips, and it could be worth to modify the R-108 as an ultra-light radio for MW DXing even though there are some minor problems as follows.

どちらの受信機も、中波ローカル局は良く受信してくれます。受信電圧や受信SN比に関して、両者に大きな違いは感じません。しかし、受信レベルが低く、フェーディングが伴う信号の受信においては、RADIWOW R-108の方がTECSUN PL-380と比較して受信音がとても自然です。こういった場合のTECSUN-380の受信音は弾んでいるようなフラッタリングを伴った音になります。私はこの音は好きではないですね。
旅行先の中波局受信にRADIWOW R-108はいい相棒になると思います。また以下に述べるマイナーな問題はありますが、中波DX用のウルトラ・ライトラジオへの改造についてもやってみる価値はあるかと思います。

  Several minor problems observed in "MY" RADIWOW R-108.
私が購入したRADIWOW R-108には、次のマイナーな問題がありました。
  • Strange noise sound syncronizing RSSI indicator like " Tik-Tik"
  • This noise is also be heard in AIR band too.  Please watch the video below.

  • Strange signal attenuation about 10-15 dB after BAND selection 
  • When I push the BAND button and change the band like MW->SW-> AIR-> FM-> LW-> MW, the received signal level is attenuated to 10-15dB. After turning off the R-108 and turning on it, the signal level is recovered.

Photo 5. MW reception test in my room
(No-interference for RSSI between the two receivers was observed.)

Figure 7. Comparison of RSSI of received MW radio stations
(The maximum value in about 20-seconds observation)

Figure 8. Comparison of SN ratio of received MW radio stations
(The maximum value in about 20-seconds observation)
The SN ratio indication of MW reception seems to be up to 25 dB.