SECRET
  
 
O.N.S. 5             
 
APPENDIX G.  (H/F & M/F D/F REPORT
                                                                                                                         8th May, 1943.  
     
          Report on U-boat transmissions received by Escort Group B7 between 22nd April and 8th May, 1943.  Ships fitted with H/F D/F were:  
          H.M.S. DUNCAN with FH4  
          H.M.S. TAY           with FH3  
          H.M.S. ORIBI        with FH3 joined the group on 30th April.  
          S.S. MERTON, a merchant ship in the convoy, was fitted with FH3, but was not calibrated and had no H/F D/F operators on board.  
          H.M.S. DUNCAN left the convoy on 3rd May.  
          Until April 30th H.M.S. DUNCAN and TAY kept D/F watch on Series 1 and listening out watch on Series 8 and Series 7 respectively.  When H.M.S. ORIBI joined she kept D/F watch on Series 7 and H.M.S. TAY changed to Series 8, H.M.S. DUNCAN remaining on Series 1 until 2300Z/30 when D/F watch transferred to Series 8 which the U-boats closest to the convoy appeared to be using.  Listening watch was still kept on Series 1 as far as atmospheric conditions permitted.  On 3rd May H.M.S. TAY transferred D/F watch to Series 2 line 2 and on the 4th May to Series 2 line 2, H.M.S. ORIBI keeping Series 2 line 2.  These two lines appeared to be used by two distinct sets of U-boats.  Between 1500Z/4 and 2100Z/5 bearings on line 1 were mainly to port of the convoy (course 190°), and those on line 2 to starboard and aft.  After 2100Z/5 U-boats using line 1 were aft and on the port quarter.  From 0840/6 U-Boats using line 2 were in all quarters, specially ahead, while those using line 1 were distant on the port quarter.  
          Many fixes were obtained by H.M.S. DUNCAN from bearings passed from the TAY; and also on the 26th and 28th April it was determined that U-Boats were nearer O.N.S.5 than SC127 by fixes obtained from bearings being intercepted when passed from ships of the 4th Escort Group to EG4.  
          Fixes were not obtained on 4th to 6th May between H.M.S. ORIBI and H.M.S. TAY.  H.M.S. TAY passed warnings to change frequency on HT11 using the correct frequencies.  These were not received by H.M.S. ORIBI.  H.M.S. ORIBI made a change frequency signal once (0950/5) on 2410 kcs., enabling TAY to change frequency and obtain a fix.  This was the only fix made during these 3 days.  All bearings obtained by H.M.S. ORIBI were passed on 2410 kcs.  
          Six unidentified M/F D/F bearings were passed from Merchant ships in the convoy, and one from H.M.S. TAY who kept guard on 384 kcs. 25th April.  
          Bearings received by H.M.S. DUNCAN and TAY follow.  
          Those received by H.M.S. ORIBI are included in the Report of Proceedings of EG3 while in company of EGB7.  
          The following transmissions were received by H.M.S. DUNCAN:  Bearings strength 4 or 5 are ground ray, and those strength 1, 2 or 3 are sky ray, unless otherwise stated.  
     
     

 

 
 
     
 
SHIP - H.M.S. DUNCAN
 
   
NO.
DATE
TIME
FREQ.
BRNG.
YES OR NO SENSE
POSITION
TEXT OR PREFACE
SIG. STR.
1
24/4/43
0614
6672
-
-
58° 11'
12° 51'
N/ENIGMA
2
2
25/4/43
1836
11068
-
-
60° 14'
19° 03'
1805/25 MRSG EMCY 61
3
3
25/4/43
2154
4070
-
-
60° 20'
19° 30'
2330/25 SKGY UAAI 73
3
4
25/4/43
2305
4070
067°
Yes
60° 21'
19° 31
2235/25 99 ZNHD
3
5
25/4/43
0103
4070
-
-
60° 24'
19° 37'
0104/26 NOTHING FURTHER
5
6
25/4/43
0109
4070
-
-
60° 24'
19° 42'
2300/25 48 XXTD UZAX
3
7
25/4/43
0129
4070
-
-
60° 24'
19° 49'
BB WAZ RJZR YRLZ FG
4
8
25/4/43
0247
4070
-
-
60° 25'
19° 48'
0104/26 QRWT MPCW
3
9
26/4/43
0345
4070
-
-
60° 26'
19° 50'
BB JJT ISBA TOBK UO
3
10
26/4/43
0338
4070
-
-
60° 27'
19° 51'
0510/26 EXPY MDOO 59
3
11
26/4/43
0347
4070
-
-
60° 28'
19° 55'
BB JJT ISBA TOBK UO
3
12
26/4/43
0507
5560
-
-
60° 28'
19° 59'
BB JJT ISBA YEBM AO
2
13
26/4/43
0519
5560
-
-
60° 29'
20° 01'
0510/26 EPXY MDOO 59
4
14
26/4/43
0532
5560
-
-
60° 30'
20° 03'
BB W - TOB -
2
15
26/4/43
0533
5560
-
-
60° 30'
20° 03'
BB JJT ISBA TOBK
3
16
26/4/43
1353
11068
-
-
60° 42'
20° 32'
1515/26 then faded
2
17
26/4/43
1516
11068
-
-
60° 45'
20° 42'
1601/26 79 YXGL QILZ
4
18
26/4/43
1627
11068
-
-
60° 53'
20° 45'
W26 BYRF W27 TCXN
1
19
27/4/43
1417
11068
045°
Yes
61° 30'
24° 32'
BB QHZ
3
20
28/4/43
0125
3920
-
-
61° 40'
27° 50'
0321/WW MHJD ZZFG
4
21
28/4/43
0158
3920
-
-
61° 40'
27° 50'
BB UUQ
4
22
28/4/43
0730
8362
159°
Yes
61° 40'
29° 27'
BB
5
23
28/4/43
0747
8362
163°
Yes
61° 40'
29° 30'
BB
4
24
28/4/43
0915
11068
324°
Yes
61° 40'
29° 52'
1050/28 N/ENIGMA
4
25
28/4/43
1050
11068
-
-
61° 30'
30° 18'
MNJI VX NOULC
5
26
28/4/43
1203
11068
225°
Yes
61° 38'
30° 34'
BB
27
28/4/43
1310
11068
266°
Yes
61° 36'
30° 48'
BB
28
28/4/43
1423
11068
276°
Yes
61° 36'
31° 22'
NAVAL ENIGMA
4
29
28/4/43
1434
11068
046°
Yes
61° 37'
31° 24'
1601/28 FKHN
5
30
28/4/43
1540
11068
288°
Yes
61° 39'
31° 29'
UNIDENTIFIED
5
31
28/4/43
1757
11068
085°
Yes
61° 44'
32° 10'
1850/28
4
32
28/4/43
1842
11068
011°
Yes
61° 43'
32° 30'
BB
5
33
28/4/43
1948
6672
285°
Yes
61° 41'
32° 40'
TUNING SIGNAL
5
34
28/4/43
2036
6672
108°
Yes
61° 38'
32° 43'
BB
4
35
28/4/43
2051
6672
201°
Yes
61° 38'
32° 43'
BB
4
36
28/4/43
2052
6672
223°
Yes
61° 37'
32° 37'
BB
5
37
28/4/43
2110
4070
194°
Yes
61° 37'
32° 37'
TUNING SIGNAL
4
38
28/4/43
2115
4070
070°
Yes
61° 36'
32° 50'
BB
4
39
28/4/43
2130
4070
260°
No
61° 36'
32° 50'
BB YFOF ZNIX
4
40
28/4/43
2133
4070
101°
Yes
61° 36'
32° 50'
2140/28 No Text
4
41
28/4/43
2145
4070
080°
Yes
61° 35'
32° 53'
4 LETTER CODE
4
42
28/4/43
2152
4070
176°
Yes
61° 35'
32° 53'
WW PGZR R . . . W4 UXKN
3
43
28/4/43
2207
4070
080°
Yes
61° 35'
32° 56'
2321/28
3
44
28/4/43
2216
4070
109°
Yes
61° 34'
32° 58'
N/E 4 LETTER CODE
3
45
28/4/43
2226
4070
234°
Yes
61° 34'
33° 01'
TUNING SIGNAL
4
46
28/4/43
2228
4070
138°
Yes
61° 34'
33° 01'
TUNING SIGNAL
4
47
28/4/43
2235
4070
215°
Yes
61° 33'
33° 03'
TUNING SIGNAL
4
48
28/4/43
2236
4070
127°
Yes
61° 37'
33° 03'
BB XPF XNFX
4
49
28/4/43
2240
4070
203°
Yes
61° 37'
33° 03'
TUNING SIGNAL
4
50
28/4/43
2241
4070
223°
Yes
61° 37'
33° 03'
BB _ _ _ _ _
4
51
28/4/43
2243
4070
140°
Yes
61° 37'
33° 03'
BB _ _ _ _ _
4
52
28/4/43
2244
4070
153°
Yes
61° 37'
33° 03'
N/E
4
53
28/4/43
2248
4070
173°
Yes
61° 37'
33° 03'
TUNING
4
54
28/4/43
2250
4070
-
No
61° 37'
33° 03'
BB
2
55
28/4/43
2303
4070
164°
Yes
61° 36'
33° 08'
BB UUQ XELB WH
2
56
28/4/43
2312
4070
133°
Yes
61° 36'
33° 11'
TUNING
4
57
28/4/43
2314
4070
134°
Yes
61° 36'
33° 11'
BB UUK XELL WM
4
58
28/4/43
2345
4070
114°
Yes
61° 35'
33° 17'
BB
4
59
29/4/43
2347
4070
144°
Yes
61° 35'
33° 17'
BB
4
61
29/4/43
0241
4070
-
No
61° 31'
34° 03'
BB
2
62
29/4/43
0518
5560
163°
Yes
61° 28'
34° 37'
TUNING
5
63
29/4/43
0538
5560
264°
Yes
61° 27'
34° 31'
BB
5
64
29/4/43
0546
5560
134°
Yes
61° 26'
34° 42'
0401/29 38 N/E
5
65
29/4/43
0557
5560
192°
Yes
61° 26'
34° 45'
BB
5
66
29/4/43
0634
6672
138°
Yes
61° 25'
34° 50'
TUNING (SKY)?
5
     
     

 

 
 
     
 
SHIP - H.M.S. DUNCAN
 
   
NO.
DATE
TIME
FREQ.
BRNG.
YES OR NO SENSE
POSITION
TEXT OR PREFACE
SIG. STR.
67
29/4/43
0640
6672
126°
Yes
61° 24'
34° 52'
BB 5
68
29/4/43
0825
8362
214°
Yes
61° 19'
35° 11'
TUNING 5
69
29/4/43
0828
8362
127°
Yes
61° 19'
35° 11'
BB 5
70
29/4/43
1130
11068
-
No
61° 11'
35° 56'
BB  NO TEXT 2
71
29/4/43
1133
11068
-
No
61° 11'
36° 07'
BB  NO TEXT 2
72
29/4/43
1311
11068
339°
Yes
61° 08'
36° 09'
1401/29  38  N/E 5
73
29/4/43
1319
11068
-
No
61° 07'
36° 12'
BB 2
74
29/4/43
1345
11068
102°
Yes
61° 07'
36° 14'
BB 4
75
29/4/43
1402
11068
098°
Yes
61° 06'
36° 15'
BB 4
76
29/4/43
1419
11068
030°
Yes
61° 05'
36° 17'
N/E 4
77
29/4/43
1442
11068
207°
Yes
61° 05'
36° 17'
N/E 4
78
29/4/43
1445
11068
-
No
61° 05'
36° 17'
-320/29 2
79
29/4/43
1826
11068
015°
No
61° 01'
36° 32'
TUNING 5
80
29/4/43
1835
11068
163°
Yes
61° 01'
36° 32'
1803/29 69 QRPR QIHE 4
81
29/4/43
1842
11068
127°
Yes
61° 01'
36° 32'
0410/29 38 RFMS VRKN 5
82
30/4/43
0107
4070
234°
Yes
60° 46'
37° 05'
0201/30 NO TEXT 4
83
30/4/43
0127
4070
092°
Yes
60° 45'
37° 06'
TUNING (GROUND RAY) 3
84
30/4/43
0134
4070
116°
Yes
60° 44'
37° 07'
TUNING 3
85
30/4/43
0135
4070
104°
Yes
60° 44'
37° 07'
0241/30 NO TEXT (G/RAY) 3
86
30/4/43
0142
4070
096°
Yes
60° 43'
37° 08'
TUNING 3
87
30/4/43
0147
4070
240°
No
60° 43'
37° 08'
?/30 G/RAY 3
88
30/4/43
0158
4070
111°
Yes
60° 42'
37° 10'
0241/30 G/RAY 3
89
30/4/43
0418
4070
070°
Yes
60° 36'
38° 47'
-2/30 69 ? -JON 2
90
30/4/43
1530
11068
348°
Yes
60° 14'
38° 47'
1401/30 38 CDOU 3
91
30/4/43
2047
6672
138°
Yes
59° 55'
39° 10'
2221/30 51 UPEA BOPJ 3
92
30/4/43
2342
4600
144°
No
59° 49'
39° 19'
WW  WW 3
93
1/5/43
0042
4600
234°
Yes
59° 47'
39° 21'
0120/1 G/RAY 3
94
1/5/43
0210
4600
310°
Yes
59° 45'
39° 26'
TUNING G/RAY 3
95
1/5/43
0211
4600
310°
No
59° 45'
39° 26'
B  
96
1/5/43
0221
4600
300°
No
59° 45'
39° 26'
TUNING SKY/WAVE 3
97
1/5/43
1511
12950
208°
No
59° 33'
39° 57'
WW  WW 2
98
1/5/43
1715
12950
-
-
59° 32'
40° 04'
1020/1  91 3
99
1/5/43
2028
7645
130°
Yes
59° 30'
40° 13'
TUNING SKY/WAVE 3
100
1/5/43
2141
7645
002°
No
59° 29'
40° 18'
-/1  22 N/E SKY/WAVE 1
101
1/5/43
2150
7645
-
No
59° 29'
40° 18'
 2200/1 N/E SKY/WAVE 1
102
1/5/43
2228
4600
345°
No
59° 29'
40° 19'
-/1 38 N/E SKY/WAVE 1
103
1/5/43
2300
4600
190°
Yes
59° 28'
40° 21'
BB GROUND WAVE 3
104
1/5/43
2305
4600
211°
Yes
59° 28'
40° 21'
BB GROUND WAVE 3
105
1/5/43
2310
4600
192°
Yes
59° 28'
40° 21'
BB GROUND WAVE 3
106
1/5/43
2320
4600
165°
Yes
59° 28'
40° 22'
-/1 N/E GROUND WAVE 3
107
2/5/43
0500
6180
-
-
59° 21'
40° 49'
TUNING 2
108
4/5/43
2248
5650
160°
Yes
51° 34'
43° 48'
BB FMS HEXX VUQS 3
109
5/5/43
0008
5650
331°
Yes
51° 20'
43° 48'
0128/5 -1 LSSE TOHJ 4
110
5/5/43
0140
5650
040°
Yes
51° 04'
43° 48'
0320/5 --KW WFRX 3
111
5/5/43
0200
5650
-
-
50° 55'
43° 48'
BB YDT KJUR 2
112
5/5/43
0354
5650
358°
Yes
50° 30'
43° 48'
0434/5 64 OPNX KAZR 2
113
5/5/43
0410
5650
006°
Yes
50° 26'
43° 48'
0533/5 71 OPGU NUFX 2
114
5/5/43
0418
5650
003°
Yes
50° 25'
43° 48'
0533/5 71 OPGU NUFX 2
115
5/5/43
0421
5650
004°
Yes
50° 24'
43° 48'
BB LXK GU11 2
     
     

 

 
 
     
  H.M.S. "DUNCAN" FH 4.  
          At 1000Z on 25th April, 1943, the shaft of the sense switch broke at its connection to the rod supporting the three aerial lead sense switches which lies along the bottom of the set.  This was due to the switch connected to the sense aerial leads jamming.  The shaft was repaired and the set working by 2240Z and the set appeared normal until 0030Z when the two small metal contacts on the rotatable part of the sense aerial leads sense switch came out of place.  This fault was not rectified until 0821Z/27th April when the F. & A. sense worked satisfactorily but no R. & S. sense was obtained.  It was then decided to leave the set as it was as U-Boats appeared to be transmitting in the vicinity.
          It is considered that the sense aerial lead sense switch was of faulty construction, and that the shaft of the sense switch parted under not heavy pressure.  The design of the set did not facilitate easy repair, especially in a heavily rolling ship.
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     

 

 
 
  SECRET  
 
HF/DF REPORT.
 
   
          Report on U-Boat transmissions received by H.M.S. TAY on HF/DF set FH3 with auxiliary receiver B28 between 24.4.43 & 8.4.43 Headings as in CAFO 1515/42.
     
  Distribution:  S.O. B7 Escort Group 1 copy  
                      Commanding Officer, H.M.S. TAY 1 copy & spare copy.  
     
 
 
a.
b.
  
c.
d.
e.
f.
  Ap. 24.         North & West Type, if ground ray.
1. 0225
3920
   313 Yes 57 48 12 17 WW No
2. 1656
10300
   200 Yes 58 40 14 25 1630/24 No
3. 2010
6675
   B 28   58 53 14 58    
4. 2025
6675
   150 Yes 58 54 15 00 2203/24 No
5. 2033
6675
   No Zero 58 56 15 03 2030/24 No
6. 2048
6675
   No bg.   58 58 15 06 2114/24 No
7. 2050
6675
   No bg.   58 58 15 06 B Bar No
8. 2335
4070
   No bg.   59 09 15 37 WW No
9. Ap. 25.
             
  1034
11068
   B 28   59 50 18 00 1112/25  
10. 1917
6300
   313 Yes 60 17 19 14 Longs No
11. 2303
4070
   301 Yes 60 26 19 34 2357/25 Yes
12. Ap. 26
             
  0250
4070
   263 Yes 60 33 19 58 0104/26 No
13. 0335
4070
   206 Yes 60 34 20 03 0516/26 No
14. 0346
4070
   No bg.   60 35 20 05 B Bar No
15. Ap. 27
             
  1820
7645
   B 28   60 55 20 52 1844/27  
16. Ap. 28
8362
   No bg.   61 42 29 30 B Bar No (Time 0928)
17. 0744
8362
   189 Yes 61 41 29 34 B Bar No
18. 0914
11068
   215 Yes 61 41 29 57 1040/28 Yes
19. 1051
11068
   059 Yes 61 41 30 22 B Bar No
20. 1202
1168
   236 Yes 61 40 30 41 B Bar Yes
21. 1311
11068
   260 Yes 61 38 31 00 B Bar Yes
22. 1428
11068
   277 Yes 61 39 31 21 1602/28 Yes
23. 1541
11068
   280 Yes 61 42 31 40 1713/28 Poor Zero
24. 1752
11068
   171 Yes 61 57 32 13 1850/28 Yes
25. 1841
11068
   277 Yes 60 50 32 23 B Bar Yes
26. 2034
6675
   229 Yes 61 45 32 50 B Bar Yes
27. 2050
6675
   230 Yes 61 44 32 56 B Bar Yes
28. 2051
6675
   230 Yes 61 44 32 56 B Bar Yes
29. 2115
4070
   105 Yes 61 42 33 03 B Bar Yes
30. 2233
4070
   236 Yes 61 38 33 23 B Bar Yes
31. 2130
4070
   080 Yes 61 42 33 07 B Bar 2nd Class
32. 2152
4070
   192 Yes 61 40 33 12 WW 2nd Class
33. 2219
4070
   - -   61 39 33 20 Shifting Zero 2321/28
34. 2236
4070
   236 Yes 61 38 33 23 B Bar Yes
35. 2241
4070
   212 Yes 61 38 33 25 B Bar Ground Ray Yes
36. 2247
4070
   180 Yes 61 38 33 25 B Bar Yes
37. 2249
4070
   041 Yes 61 38 33 26 B Bar Yes
38. 2314
4070
   225 Yes 61 37 33 50 B Bar Yes
39. 2343
4070
 No Zero 61 35 33 36 B Bar Yes
40. Ap. 29
             
  0048
4070
   175 Yes 61 30 33 38 Key clicks  
41. 0510
4070
   200 Yes 61 27 34 29 Longs Yes
42. 1012
4068
   092 Yes 61 30 33 30 1030/29 2nd Class
43. 1257
11068
   065 Yes 61 04 36 09 0320/29 No
44. 1323
11068
   200 Yes 61 03 36 15 1401/29 Yes
45. 1337
11068
   068 Yes 61 03 36 17 0320/29 Yes
46. 1341
11068
 No Zero 61 03 36 18 B Bar Yes
47. 1402
11068
   165 Yes 61 01 36 24 B Bar No
48. 1414
11068
 No Zero 61 00 36 29 1445/29 No
49. 1836
11068
   169 Yes 61 11 35 30 1903/29 No
50. 1845
11068
   235 Yes 61 14 35 23 0410/29 No
51. 1951
6675
   281 Yes 61 11 35 37 2045/29 No
52. Apr.30
             
  0255
4600
   069 Yes 60 45 37 25 2345/29 No
53. 0529
5560
   150 Yes 60 31 38 00 B Bar No
54. 1410
12950
 No bearing 60 18 38 32 1521/30 No
55. 1500
12950
 No bearing 60 15 38 40 1630/30 No
 
     
     

 

 
 
     
 
 
a.
b.
  
c.
d.
e.
f.
            North & West  
56. 1705
12950
   B 28   60 09 38 58 1751/30 No
57. 2038 7645   No Bearing 60 05 39 08 B Bar  
58. 2104 7645   No Bearing 60 02 39 10 B 28 No
59. 2125 7645   176 Yes 60 02 39 10 2221/30 - -
60. 2331 4600   197 Yes 59 59 39 14 0120/1 - -
61. 2336 4600   No Bearing 59 59 13 14 WW - -
62. 2337 4600   169 Yes 59 59 39 14 Longs - -
  May 1st.                
63. 0034 4600   187 Yes 59 57 39 15 0120/1 - -
64. 0125 4600   No bearing 59 55 39 17 B Bar - -
65. 0127 4600   No bearing 59 55 39 17 B Bar - -
66. 0135 4600   170 Yes 59 55 39 18 B Bar - -
67. 0142 4600   162 Yes 59 54 39 18 B Bar Yes
68. 0146 4600   162 Yes 59 54 39 18 B Bar Yes
69. 0218 4600   No Bearing 59 53 39 20 B Bar No
70. 0325 4600   No Bearing 59 51 39 24 WW No
71. 2138 4645   No Bearing 59 25 40 05 2210/1 Preamble only
72. 2207 4600   214 Yes 59 22 40 09 2301/1  
73. 2308 4600   No Bearing 59 21 40 13 0043/2 Preamble only
74. 2310 4600   No Bearing 59 20 40 12 B Bar No
75. 2243 4600   228 Yes 59 21 40 11 2201/1  
  May 2nd.              
76. 0147 4600   No Bearing 59 12 40 28 2301/1 QSA  IMI
77. 0209 4600   194 Yes 59 11 40 30 Longs No
78. 0219 4600   189 Yes 59 10 40 31 0043/2 Preamble only
79. 0242 4600   173 Yes 59 10 40 33 0043/2  
80. 0410 4600   188 Yes 59 06 40 39 0012/2 QSA  IMI
81. 0423 4600   170 Yes 59 05 40 38 0012/2  
82. May 3rd.                
  2140 10510   No Bearing 58 25 41 28 2314/3 No
83. 2200 5650   B 28   58 21 41 30 B Bar No
84. 2300 5650       58 15 41 33 Continuous tiddly e's
85. May 4th.                
  1419 12215   B 28   56 12 42 12 B Bar No
86. 1451 12215   B 28   56 07 42 15 B Bar No
87. 1546 12215   125 Yes 56 03 42 18 B Bar Yes
88. 1553 12215   238 Yes 56 02 42 19 B Bar Yes
89. 1558 12215   121 Yes 56 01 42 20 Key pressing Yes
90. 1611 12215   142 Yes 55 49 42 21 B Bar Yes
91. 2213 5650   173 Yes 55 20 42 48 B Bar 2nd Class
92. 2233 5650   No Bearing 55 19 42 50    
93. 2258 5650   072 Yes 55 17 42 52 B Bar Yes
94. May 5th.                
  0113 5650   No Zero 55 13 42 54 B Bar No (55 13 42 54)
95. 0147 5650   042 Yes 55 11 42 56 B Bar No
96. 0204 5650   038 Yes 55 10 42 57 B Bar No
97. 0231 5650   085 Yes 55 07 42 58 B Bar No
98. 0305 5650   141 Yes 55 04 43 00 WW No
99. 0310 5650   145 Yes 55 03 43 01 WW No
100. 0358 5650   132 Yes 55 00 43 04 0534/5 No
101. 0415 5650   068 Yes 54 55 43 08 0533/5 No
102. 0419 5650   138 Yes 54 54 43 07 0533/5 U Boat acing as link
103. 0503 5650   100 Yes 54 50 43 14 05125 No
104. 0508 5650   150 Yes 54 49 43 15 0512/5 U Boat acting as link
105. 0716 7812   284 Yes 54 37 43 28 B Bar No
106. 0950 10510   144 Yes 54 21 43 45 B Bar No
107. 1036 12215   060 Yes 54 17 43 50 1049/5 Yes
108. 1221 12215   B 28   54 06 44 02 B Bar No
109. 1235 12215   054 Yes 54 04 44 03 1403/3 Yes
110. 1553 12215   198 Yes 53 44 44 26 B Bar Yes
111. 1715 12215   145 Yes 53 38 44 34 B Bar Yes
112. 1735 12215   070 Yes 53 35 44 35 B Bar Yes
113. 1804 12215   045 Yes 53 31 44 39 1242/5 No
114. 1908 12215   120 Yes 53 24 44 46 B Bar Yes
115. 2040 7812   181 Yes 53 20 44 49 B Bar Yes
116. 2046 7812   156 Yes 53 20 22 49 B Bar Yes
117. 2053 7812   122 Yes 53 20 44 49 B Bar Yes
     
     

 

 
 
     
 
 
a.
b.
  
c.
d.
e.
f.
118. 2111
7812
   033 Yes 53 30 44 49 B Bar Yes
119. 2153 7812   029 Yes 53 20 44 29 2200/5 Ground Ray Yes
120. 2235 5650   320 Yes 53 02 44 38 B Bar Yes
121. 2240 5650   330 Yes 53 01 44 38 B Bar Yes
122. 2250 5650   150 Yes 52 59 44 50 B Bar Yes
123. 0110 5650   107 Yes 52 44 45 00 0110/6 Yes
124. 0209 5650   099 Yes 52 36 45 00 0333/6 Yes
125. 0253 5650   099 Yes 52 32 44 57 0411/6 Yes
126. 0253 5650   025 Yes 52 29 44 55 0435/6 Yes
127. 1024 12215   043 Yes 51 44 45 03 0957/6 No
128. 1132 12215   035 Yes 51 37 45 06 1159/6 No
129. 1239 12215   043 Yes 51 31 45 10 WW No
130. 1424 12215   038 Yes 51 11 45 20 1600/6 No
131. 1439 12215   025 Yes 51 08 45 22 1650/6 No
132. 1513 12215   076 Yes 51 05 45 24 1513/6 No
133. 1701 12215   211 Yes 51 00 45 27 1840/6 Yes
134. 2310 5650   073 Yes 50 09 45 33 Continuous tiddly e's
  May 7th.                
135. 0105 5650   070 Yes 49 54 45 53 Continuous tiddly e's
 
   
 
MF/DF REPORT
     
  April 26th  
 
2145 410      
  approx. 148 60 41 20 40 3rd class, very doubtful.
        One group and half group at end of message only heard.
        Unreliable
 
     
  Note:  
          The B 28 receiver installed recently has been entirely satisfactory.  At times, signals audible on this receiver were inaudible on the FH3 and no bearings were obtained.  The FH3 was out of action 24th April from 0417 G.M.T. to 0917 G.M.T. owing to flooding of the supply rectifier in the W/T Office.  The "Tiddly e's Nos. 84, 134 & 135 have been heard on previous occasions.  
     
     

 

 
 
     
  The following HF/DF Bearings were reported by H.M.S. "TAY" and merchant ships:  
   
 
DATE
TIME
FREQUENCY
BEARING
SENSE
POSITION
TEXT
SHIP
1.
25/4/43
1714
327
270
Yes
60 12'
18 58'
Unident.
121
2.
26/4
2145
384
148
Yes
60 50'
21 00'
"
TAY
3.
26/4
2240
420
130
Yes
61 00'
21 15'
"
54
4.
29/4
1020
375
248
Yes
61 13'
35 40'
"
101
5.
30/4
0125
384
068
Yes
60 45'
37 06'
"
101
6.
30/4
2225
330
-
-
59 51'
39 14'
U's & Longs.
7.
1/5
0750
384
062
Yes
59 38'
39 40'
Unident.
101
     
     
     
     
     
     
     
     
     
     
     
     
     

 

 
 
     
 
REPORT ON W/T CONDITIONS IN AREA WEST OF 27°W, N. OF 56°N.
 
   
 
28th April, 1943.   61°30' N 26°00'W
  Before 2200Z   ADA: R3, KYU: R1
  2200-2300   Control fades.  U-Boats appear to have difficulty in establishing communication.  Many tuning signals.
       
29th April, 1943.   61°N 36°W
  Before 0139Z   Nothing heard.
  By 0500   Control normal and U-Boats in good communication.
  0700-1400   Change in frequency (4070 to 8362 kcs. later 11068 kcs.)  Control not heard though U-Boats appear to be in good communication.
  1400-1900   ADA: R1
  1900   Change frequency (11068 to 6672, later 4070 kcs.)  Hear nothing.
       
30th April, 1943.   60°40'N 37°00'W
  0100Z   Control not heard, but U-Boats in good communication.
  0200   ADA: R3, KYU: E1
  0500-0930   Change of frequency (4070 to 5560, later 8362)  Nothing heard.
  0930-2200   ADA: R3, KYU: R1
  After 2200   Nothing heard.
       
1st May, 1943.   59°40'N 40°00'W
  0200Z - 0300   Nothing heard except U-Boats.
  1420   Control first heard (12950 kcs.)
  2200   Control not audible, but U-Boats on 4600 kcs. till 2330Z.
       
2nd May, 1943.   39°N 41°W
  Before 1450Z   Nothing heard.  Then ADA: R2.
  1800-1900)   7645 kcs) Nothing heard.  No U-Boat transmissions.  Other times control faint.
  1930-2130)  
       
  2140-2240)   4600 kcs.)
  After 2330)  
       
3rd May, 1943.   58°N 41°W
  0420-0529Z)   Nothing heard.  No U-Boat transmissions.  Other times control faint.
  0800-1130)  
  1800-1950)  
  After 2030)  
       
4th May, 1943.    
  0015-0505Z   ADA: R3, RYU: R1
  0505-1050   Nothing heard.
  After 1050   Control heard normally.
     
     

 

 
 
     
 
REPORT ON W/T CONDITIONS IN AREA WEST OF 27°W, N. OF 56°N. (Cont'd)
 
   
          It is thought that due to bad W/T conditions in this area not all U-Boat transmissions are received by shore stations.  Admiralty signals on 28th April suggested O.N.S.5 was not being shadowed when in fact eight ground ray and many other signals had been received prior to 1200Z/28.
          U-Boats appear to have better receivers than the B28.  
     
  NOTE:  
          In all cases the frequencies and times at which control was audile agree with the Admiralty Table of Optimum Frequencies.