Hello
I've tried to remove the L-band gap on my E4000 tuner by changing the
divisors. Please see the patch below. I don't have a signal source to test
today, so i'm not sure if it works, but the pll locks. I will try to test
tomorrow.
Without my hack: E4K L-band gap: 1093 to 1233 MHz
With my hack:
sq5bpf@dellix:~/gnuradio/rtl-sdr/src$ ./rtl_test -t
Found 1 device(s):
0: ezcap USB 2.0 DVB-T/DAB/FM dongle
Using device 0: ezcap USB 2.0 DVB-T/DAB/FM dongle
Found Elonics E4000 tuner
Supported gain values (14): -1.0 1.5 4.0 6.5 9.0 11.5 14.0 16.5 19.0 21.5
24.0 29.0 34.0 42.0
Benchmarking E4000 PLL...
[E4K] PLL not locked for 51000000 Hz!
[E4K] PLL not locked for 2186000000 Hz!
E4K range: 52 to 2185 MHz
E4K L-band gap: 0 to 0 MHz
Regards
Jacek / SQ5BPF
--- tuner_e4k.c.orig 2012-11-08 22:08:07.000000000 +0100
+++ tuner_e4k.c 2012-11-08 23:01:05.000000000 +0100
@@ -35,6 +35,7 @@
/* If this is defined, the limits are somewhat relaxed compared to what the
* vendor claims is possible */
#define OUT_OF_SPEC
+#define HACKED_DIVISORS
#define MHZ(x) ((x)*1000*1000)
#define KHZ(x) ((x)*1000)
@@ -357,7 +358,14 @@
{KHZ(350000), (1 << 3) | 1, 8},
{KHZ(432000), (0 << 3) | 3, 8},
{KHZ(667000), (0 << 3) | 2, 6},
- {KHZ(1200000), (0 << 3) | 1, 4}
+#ifdef HACKED_DIVISORS
+/* the original settings seem to be ripped from some Elonics driver,
+ * however changing them a bit removes the L-band gap
+ * change this to a bit more then the end of your L-band gap --sq5bpf */
+ {KHZ(1270000), (0 << 3) | 1, 3}
+#else
+ {KHZ(1200000), (0 << 3) | 1, 4}
+#endif
};
static int is_fvco_valid(uint32_t fvco_z)