By Mac Obara/ P.Eng. - Applied Science
TZ6JA, ex-JA8SLU, PO Box59 Tama, Tokyo 206

This is the summary of my contribution of the same title written in Japanese to 
the monthly DX magazine Five Nine, June, August, and September editions 2004, pu
blished in Tokyo.

The main points are as follows; it is considered that Long Delayed Echoes (LDEs)
 will exist actually, it is neither hoax nor mystery and it will be obvious that
 LDEs is one of physical phenomena whatever the time length of delaying will be 
unusual. And also it would be reasonable to consider hypothetical ionosphere in 
the space.

Various types of LDEs have been recognized. This study has focused on the very l
ong LDEs occurred on the 1.8/3.5 MHz bands which was reported by several Japanes
e radio amateurs as a core during 1989~2004.The detail are in the attached sheet.
Those who reported their own experience of LDEs are the following well known top
 banders and/or low banders for the last30 years; H.Kanamori JA7SN, S.Sakairi JA
1HQT, H.Ogishima JA1CGM, Y.Saito JA8DNV, and Y.Nakanishi JA3ONB.

All of them except Y.Saito JA8DNV received LDEs several times. Y.Nakanishi JA3ON
B received double echoes with very long interval of 48 hours for only one transm
ission, having QSB, distortion of the signal, and Doppler shift of +300 ~-200Hz 
on 1822.0 kHz!
H.Kanamori JA7SN made reproduction of LDEs twice on 3.5 MHz CW, and he succeeded
 to tape-record one of them. To make a reproduction is indispensable step to dis
tinguish reality from human illusion.
 
These records except UL7GW indicates very long delayed time for 20 minutes up to
 82 hours. Converting these time to the distance, it will be corresponding to th
e return trips of 1.8 ~ 297 Au (Astronomical Unit, 1AU=150 million Kms.). These 
delaying time suggest us hypothetical interplanetary ionosphere composed of nume
rous magnetic and plasma tails of small planets and debris would be located main
ly at the minor planet belt and the Kuiper belt.

The season we can receive LDEs is limited from October to February, and suitable
 time of the transmission is also limited to the time from 20:00 to 22:00 Local 
Time (LT).
Time of the reception is from 16 to 06LT through the night. Signal strength of L
DEs is stable but not so strong as swinging the needle of S- meter, indicating R
ST 559 in average. We can't receive LDEs anytime. It is concentrated to some spe
cified periods and time. Sometimes LDEs has shown signal distortion, Doppler shi
ft, and double echoes. Duration of the receiving signal keeps up to 20 minutes a
t max.

LDEs has occurred during the period of one to two years after the sun spot peak 
till the bottom and one to two years before the peak. LDEs occurs, corresponding
 to the recurrent geomagnetic double peak, and also corresponds to one sixth of 
the coronal mass ejection (CME) of the sun. Even through the rest of five sixth 
does not influence to the earth, it contributes to the forming interplanetary io
nosphere as a reflector.

It seems the locations of these reflectors are to be designate astronomically. W
herever it is, specified belt and specified planets are there. As shown on the t
able, the reflectors of the type ‡U and ‡V are located at specified belts called
 mean motion resonance belt where there are so many minor planets and fragments 
of planet called debris. These reflectors should be called interplanetary ionosp
here, which are thought to be perpendicular to the ecliptic disc forming the wal
l. These small planets are prototypes of the comet, ice ball planet.

There is no such term as interplanetary ionosphere, because no such concept or n
ecessity has been required. Without this term and the concept, nobody can explai
n this type of LDEs. I believe this type of ionosphere would be existed in the s
pace. There are so many circumstantial evidences and a plasma tail of the comet 
has the key for these.

As I mentioned before, LDEs does not occur anytime. When it occurs, LDEs has cer
tain pattern concentrating to specified period and time. The key to be generated
 LDEs will belong probably to CME and the solar flare.

The fact that the best time of the transmission is around 21 LT means at this ti
me, at these season, the ecliptic line, the center of radio window, and also a c
enter of geomagnetic tail altogether concentrates at the zenith high above the s
ky. Be aware that sometimes LDEs can not be received on the frequency because of
 a Doppler shift.

In case of transmission and reception of LDEs, the following dependencies has be
en recognized through the experience.

Local time dependence(d)
Radio window d.
Seasonal d.
Solar cycle d.


Those who have experience of LDEs know there are little distance loss of the pro
pagation. In the report of Y.Nakanishi JA3ONB, we can find some evidence to be j
ustified as physical phenomena, which should be formed only in the space, neithe
r hoax nor mystery, also being imposed on his receiving signal. It is his own ke
ying habit, Doppler shift shown +300~-200Hz, that is to say, fluttering at appar
ent speed to the earth will be +25~-17Km/s occurring only in the space.
 I found that the frame of the theory of 1.8/3.5 type LDEs is in a radar equatio
n. I deemed the both LDEs and EME (moon bounce communication) are in the same ca
tegory and studied theoretically the both comparing each other. 
As a consequence of this study, I have seen that LDEs will be realistic to occur
 and the LDEs of 45 billion Kms has a priority to propagate compared with EME of
 380 thousand Kms in spite of remarkable difference of the both.

The main reasons for the distance loss of propagation is in the case of EME, whi
ch distance loss is proportional to the fourth power of the distance (r  ), on t
he other hand, LDEs has different distance loss proportional to only square of t
he distance ( r  ).

In conclusion, the long delayed echoes (LDEs) is neither hoax nor mystery, it is
 physical phenomenon. The LDEs shows us it is enable to present new concept and 
device to observe and to study the deeper place of this planet system at real ti
me.

This is a tape recorded LDEs by H. Kanamori/JA7SN:

He made QSO with NK8B and W8UVZ on 3504kHz CW around 21:10JST(LT) of Feb. 24, 19
88.  And around 22:00JST of the same day approximate 50 minutes later.  He heard
 only echoes of his transmission.  Both US signals were missing(left out).  QRM 
from JA8DNV CQ call included.  In his previous case of one day after LDEs on 3.5
MHz CW of Dec. 26, 1993.  Also he couldn't hear any party's echo such as N0ABA, 
W5AL, W7CQW, and JH1GNY on Dec. 26, 1998.  From 21:41 to 22:40JST the same thing
 occurred one day after.  All the while of the QSO with N5LU, W1FV, nothing hear
d their echoes but heard only his own echoes.  And then echoes had been faded ou
t.  Quite similar to the case of W6WYW.