Modification and TEST  RESULTS 
of BLC8G22LS-450 pallet for QO-100


my goal for this work:
 
I got some pallets from mobile base stations originally made for the 2.1-2.2GHz
range and tried to modify it for the use on QO-100 (DATV).
This is not easy because the pallet uses an internally matched power transistor
BLC8G22LS-450AV which is very narrowband and it is an
  ASYMMETRICAL DOHERTY DESIGN. The amplifier gives more than 150W
output on the original frequency or after modification for 2320MHz.
But for the use on 2.4GHz it is difficult ... there is an big loss of performance.
After some analysis of the circuit and some testet modifications

it was possible to tune the amplifier to a gain peak on 2405 MHz.
The maximum output reaches about 75W in DVB-S2 mode and with good signal quality.

NOTE:
there was no need to change the bias circuit, so the
temperature compensated bias is in original state and working well!
AND NOT ONLY THE SIMPLE MOD GIVEN BY BATC (G7NTG)
IS NEEDED YOU HAVE TO MODIFY SOME MORE THAT IT WORKS!

pallet
i got the following results


modification of the driver input (MW7IC2240)
VSWR in range 1.7-2.7GHz after modification (c) by dg0opk V1.0

 

measured GAIN, OUTPUT, CURRENT  and EFFICIENCY
of the complete module
after modification (c) by dg0opk V1.0


QRG: 2408MHz DC 28V
input (dBm)
output (dBm)
output (W)
gain (dB)
current (A)
efficiency (%)
-19
19.4
0.087
38.4
1.5

-9
29.9
0.977
38.9
1.8

-4
24.8
3.02
38.3
2.3

1
40.0
10.0
39.0
3.3
10.8
4
43.0
20.0
39.0
4.4
16.2
6
45.0
31.6
39.0
5.5
20.5
7
45.7
37.1
38.7
6.0
22.1
8
46.4
43.6
38.4
6.7
23.2
9
47.0
50.1
38.0
7.5
23.8
10
47.7
58.8
37.7
8.4
25.0
11
48.0
63.1
37.0
9.2
24.4
13
48.7
74.1
35.7
11.0
24.1

  I tested the amplifier module now over some weeks also running longtime
transmissions in DVB-S2 via OQ-100 with up to 75W output.
(green marked in the table the best range for use on DATV DVB-S2 mode)

ALL IS WORKING VERY STABLE and with GOOD SIGNAL QUALITY


update 2.april 2022
made some tweaks on one an other pallet and got some more gain and output

measured GAIN, OUTPUT, CURRENT  and EFFICIENCY
of the complete module
after modification (c) by dg0opk V1.2


QRG: 2408MHz DC 28V
input (dBm)
output (dBm)
output (W)
gain (dB)
current (A)
efficiency (%)
-20
20.8
0.12
40.8
1.5

-10
30.6
1.2
40.6
1.7

0
41.3
13.5
41.3
3.8
12.7
3
44.7
29.5
41.7
5.5
19.5
5
46.4
43.6
41.4
7.0
22.2
6
46.9
49.0
40.9
7.4
23.6
7
47.2
52.5
40.2
8.0
23.4
8
48.0
63.0
40.0
9.3
24.1
9
48.3
67.6
39.3
10.0
24.1
10
48.7
74.1
38.7
11.0
24.0
11
49.2
83.1
38.2
12.3
24.1
12
49.8
95.5
37.8
13.8
24.7
13
50.0
100.0
37.0
14.6
24.4
14
50.4
109.6
36.4
16.0
24.4


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last change: 3. april 2022 (DG0OPK)