Very good tropo and great activity in analogue modes at good old 144MHz
The RSGB contest starting 1 hour later has very high participation.
in the end several contact numbers were over 200 like SK7MW
Took my old Braun SE400 back from the shelf.
It is sensitive low noise has just few internal generated birdies
No CAT connection in 1970 RF out is just below 10W.
So i had a handwritten log like in the 70'ties..
It can be modified replacing the old hot TTL frequency counter unit box right (5V 2A...)
And install a PLL controller including CAT connection to connect it to N1MM logger. And WSJT-x
On top new 5ele 4M - 7ele 2m duoband Below 7 ele 6m yagi home brew
Just in time this 4m / 2m duoband was ready in the mast that evening.
Based upon DK7ZB 4m 5 ele and VHF 3 band design.
btw last weekend UKSMG contest Martin IS0/DK7ZB 9++ signal...
I wanted to replace my 3 band mini beam with a bigger 2 band 4M 2M no 6M elements
Avoiding the risk to pick up too much RF from the 7ele 6m yagi below on the 2m set.
Added 7 144MHz elements that fits on the existing boom.
The element sizes are based upon DK7ZB designs .
and the PA0MS legendary 2 beam i have broken one and missing 1 element
By adjusting the 2M element positions archived good match 1 : 1.5 for both 2 and 4m
Adding 2m elements will not affect the 4m tuning much
The 2m tuning impedance is affected by the longer 4m elements.
The Antenna is fed 50Z without balun at the 4m dipole
Found the best matching with 2m parasitic radiator 3.5cm close to the 4m driven element that brought the SWR down to 1: 1.5
The empirical found positions of 2m elements differ quite much from the ZB 3band element spacing.
All elements are 10mm tube except the last 2M director an old Veron beam element i had left.
Elements are isolated from the boom using Stauf clamps 10mm for 4m
and some smaller 10mm element holders.
Fixed to the 20mm square boom 3m10 with 2 crossed Tyrap's (Tireps?)
Filed a 3mm deep 20mm wide slot in the Stauff clamps to keep them square to the boom.
With the advantage that they can be fixed without drilling and element spacing can be optimized.
Critical positions are the radiator and the first 2 directors.
With hand effect checking the SWR i saw that the 2m radiator rf was distributed symmetrical.
No no use for a bal-un but i kept the last part of coax free from the boom.
The first director is most sensitive it must be clear from other metal or even myself .
The SWR raised when approaching it.
I could not see any SWR change when touching the reflector.
Not even by touching it with an element rod.
2m reflector must have its function for F/B ratio
this has to be tested on a near field signal and then placing removing the reflector, would be interesting to see if the books are right.
Resume
The few year ago made DK7ZB mini 3band antenna performs good for it's small size 1m25.
It can easy stay in the mast and survive the winter season.
But the long 7 element 6m clearly picks up less noise from the neighbor Solar power installation.
On the DK7ZB mini beam the S-meter started to increase already halfway to the noise source
at 50m probably radiated up from below.
The 7ele 9m yagi starts picking up noise first at about 10 dgs from the noise source.
That brought down the 50MHz noise level a lot.
This Solor Edge PV SE8k converter was professional tested again by A.T.
EMC department of Telecom. And it failed the legal EMC norm.
So there is hope for a solution for the now over 2 year lasting RFI problem.
The fist tests with the 4/2 combi showed that it performs well
directivity is good SWR is 1: 1.5
Compared to other nearby ham's it is doing well on 2 and 4m
but since Johan PF7M is s.k. it is hard to know how good is good
By coincidence the 144MHz montly DAC started just after the antenne was up.
And with exceptional propagation
f.i. G1YBB/P IO82lb booming S9 using 10W
Super tropo DX the first test ! EI3KD in CW 1011km my old Stiveco keyer was connected
and EI3KD came back right away woow that was al long time ago I heard / worked Ireland at 2m
This tropo condition was special since the ducting did not stop at the coast as usual in summer evenings but it went deep over land.
OK1DOY 59 GI4SNA 59 GW8ASD/P GW4ZAR/P GD0AMD/P GM4AFF GM4BYF 59
I just made a super antenna ;-)
This morning 144402 OY6BEC IP62 heard S1 S2
A pleasure to listen with the Braun SE400 zapping the band..
5 of 50 QSO are confirmed in LOTW veryt few VHF hams use LOTW
The RSGB contest starting 1 hour later has very high participation.
in the end several contact numbers were over 200 like SK7MW
Took my old Braun SE400 back from the shelf.
It is sensitive low noise has just few internal generated birdies
No CAT connection in 1970 RF out is just below 10W.
So i had a handwritten log like in the 70'ties..
It can be modified replacing the old hot TTL frequency counter unit box right (5V 2A...)
And install a PLL controller including CAT connection to connect it to N1MM logger. And WSJT-x
On top new 5ele 4M - 7ele 2m duoband Below 7 ele 6m yagi home brew
Just in time this 4m / 2m duoband was ready in the mast that evening.
Based upon DK7ZB 4m 5 ele and VHF 3 band design.
btw last weekend UKSMG contest Martin IS0/DK7ZB 9++ signal...
I wanted to replace my 3 band mini beam with a bigger 2 band 4M 2M no 6M elements
Avoiding the risk to pick up too much RF from the 7ele 6m yagi below on the 2m set.
Added 7 144MHz elements that fits on the existing boom.
The element sizes are based upon DK7ZB designs .
and the PA0MS legendary 2 beam i have broken one and missing 1 element
By adjusting the 2M element positions archived good match 1 : 1.5 for both 2 and 4m
Adding 2m elements will not affect the 4m tuning much
The 2m tuning impedance is affected by the longer 4m elements.
The Antenna is fed 50Z without balun at the 4m dipole
Found the best matching with 2m parasitic radiator 3.5cm close to the 4m driven element that brought the SWR down to 1: 1.5
The empirical found positions of 2m elements differ quite much from the ZB 3band element spacing.
All elements are 10mm tube except the last 2M director an old Veron beam element i had left.
Elements are isolated from the boom using Stauf clamps 10mm for 4m
and some smaller 10mm element holders.
Fixed to the 20mm square boom 3m10 with 2 crossed Tyrap's (Tireps?)
Filed a 3mm deep 20mm wide slot in the Stauff clamps to keep them square to the boom.
With the advantage that they can be fixed without drilling and element spacing can be optimized.
Critical positions are the radiator and the first 2 directors.
With hand effect checking the SWR i saw that the 2m radiator rf was distributed symmetrical.
No no use for a bal-un but i kept the last part of coax free from the boom.
The first director is most sensitive it must be clear from other metal or even myself .
The SWR raised when approaching it.
I could not see any SWR change when touching the reflector.
Not even by touching it with an element rod.
2m reflector must have its function for F/B ratio
this has to be tested on a near field signal and then placing removing the reflector, would be interesting to see if the books are right.
Resume
The few year ago made DK7ZB mini 3band antenna performs good for it's small size 1m25.
It can easy stay in the mast and survive the winter season.
But the long 7 element 6m clearly picks up less noise from the neighbor Solar power installation.
On the DK7ZB mini beam the S-meter started to increase already halfway to the noise source
at 50m probably radiated up from below.
The 7ele 9m yagi starts picking up noise first at about 10 dgs from the noise source.
That brought down the 50MHz noise level a lot.
This Solor Edge PV SE8k converter was professional tested again by A.T.
EMC department of Telecom. And it failed the legal EMC norm.
So there is hope for a solution for the now over 2 year lasting RFI problem.
The fist tests with the 4/2 combi showed that it performs well
directivity is good SWR is 1: 1.5
Compared to other nearby ham's it is doing well on 2 and 4m
but since Johan PF7M is s.k. it is hard to know how good is good
By coincidence the 144MHz montly DAC started just after the antenne was up.
And with exceptional propagation
f.i. G1YBB/P IO82lb booming S9 using 10W
Super tropo DX the first test ! EI3KD in CW 1011km my old Stiveco keyer was connected
and EI3KD came back right away woow that was al long time ago I heard / worked Ireland at 2m
This tropo condition was special since the ducting did not stop at the coast as usual in summer evenings but it went deep over land.
OK1DOY 59 GI4SNA 59 GW8ASD/P GW4ZAR/P GD0AMD/P GM4AFF GM4BYF 59
I just made a super antenna ;-)
This morning 144402 OY6BEC IP62 heard S1 S2
A pleasure to listen with the Braun SE400 zapping the band..
5 of 50 QSO are confirmed in LOTW veryt few VHF hams use LOTW
| Details | PA0O | EI3KD | 2018-06-05 19:33:39 | 2M | CW | 144.19700 | IRELAND | ||
| Details | PA0O | G4KUX | 2018-06-05 19:27:19 | 2M | SSB | 144.20000 | |||
| Details | PA0O | GI4SNA | 2018-06-05 19:25:13 | 2M | SSB | 144.22600 | NORTHERN IRELAND | ||
| Details | PA0O | G8KPD/P | 2018-06-05 19:22:37 | 2M | SSB | 144.39500 | |||
| Details | PA0O | G4TMI/P | 2018-06-05 19:19:47 | 2M | SSB | 144.37100 | |||
| Details | PA0O | GM4AFF | 2018-06-05 19:17:46 | 2M | SSB | 144.34400 | |||
| Details | PA0O | OK1DOY | 2018-06-05 18:56:03 | 2M | SSB | 144.26400 | |||
| Details | PA0O | DP9X | 2018-06-05 18:44:21 | 2M | SSB | 144.21500 | |||
| Details | PA0O | G1YBB/P | 2018-06-05 18:05:48 | 2M | SSB | 144.26000 | |||
| |||||||||
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