Chuck,
Great to hear of your luck with 1220.
The baby powder on slug and coil would have helped.
I found transmitt audio to have a low level crackle.
Fix was to reroute b+ power a few cm away.
Transmitt audio with adjustment at max is still weak.
Never did fix that.
My 5 watt version produced a maximum of 3 watts even after bending
and remaking output coils.
The worst problem is rf immunity.
When I fire up the Titan I reset all the memories back
to 146.52 mhz. I installed it into the car and lost memories in
less than a week.
I live about 10 miles from a populated broadcast transmitter site.
I have noticed signal mixing in the 1220 that interferes or
causes high squelch sitting to bypass noise.
I dislike the waist of memories allocated to split operation.
It is a great packet radio.
Receive audio it very full and plesant, Just bit of extra ringing.
Like audio stage is at upper gain end of design.
I was plesant to program in it's simple way.
and it's default to 146.52 was a wonderfull idea.
A bit too wonderfull as time goes on loosing memories.
My wife build this 1220 with my over looking.
It was a great experience for both of us.
I was planing on putting it in her car.
I simply do not trust memories and dislike low transmitt audio.
We will never part with her 1220 rig.
We keep **
On Wed, 25 Jun 1997, Chuck Murcko wrote:
> Hi all. I just finished putting a 1220/1222 combination on the air. This has
> turned out to be a very nice rig, and has one of the best 2m receiver sections
> I've ever used. The exception was an old Icom with helical resonators, but
> that's another story.
>
> Construction was quite straightforward, save for a number of small hitches.
>
> 1) Things get tight at the end of assembly, when mounting the power
> transistors to the back subpanel/RF shield. Go slowly here. Same goes
> for the T-R board assembly.
>
> 2) One PEM nut was missing from a side subpanel. No big deal; the rig is
> exceptionally well engineered and solid, especially if the instructions
> to hot glue the VCO coil are followed. Case rigidity seems unimpaired by
> missing fastener.
>
> 3) Go easy on the slug in the VCO coil; mine cracked, and I had to clean it
> out and replace it with one of similar ferrite mix from the junkbox. My
> fault.
>
> 4) You really have to clip lead power to the 1222 amplifier to align it. The
> input tuning capacitor is impossible to get at when mounted for testing
> as suggested in the manual.
>
> With the amplifier, I measure 40w out at 146.000 MHz and 37w at either band
> edge. With a small dual band antenna (Cushcraft AR-270, about 4' tall)
> mounted at 18' above ground, I can reliably use repeaters up to 35-40 mi
> away, and get about 10 mi further when the band opens a bit on these summer
> evenings. Haven't experienced any tunnels or skip yet. 8^)
>
> All reports so far have remarked on the excellent transmit audio and lack of
> synthesizer noise (a *big* problem with the old Ramsey kit transceivers).
>
> The receiver is *very* good. No birdies or synthesizer artifacts are audible.
> The one thing I thought was one turned out to be a bad power line insulator
> outside. Excellent intermod performance and image rejection, too.
>
> Packet and PL work fine. It was a bit odd getting used to having simplex
> frequencies in the lower memories (The upper memories are used to store
> frequency pairs for nonstandard offsets, so any simplex frequency stored
> there is considered as one of the pairs).
>
> Is there a 440 Mhz kit in the future? This would be very nice, though harder
> to package for a kit than a 144 or 220 MHz unit.
>
> What I miss on this rig is general purpose scanning capability. Perhaps
> something like scanning between any two (or the first two) memory frequencies
> could be done in future. I can also see myself running out of memories
> eventually, though I've never used more than 30 on any ham rig I've had.
> Somehow I can't see the need for hundreds or thousands, myself. It'd be
> difficult to add too many more functions with only four pushbuttons on the
> front panel.
>
> All in all, the rig took about 25 hours to build and align, working slowly
> and carefully, though persistently. No doubt the second or third would go
> much faster. 8^)
>
> I haven't used this transceiver in the car yet, so I can't report on that
> aspect of use.
>
> All in all, a very nice rig for T-T and anyone with the time and expertise
> (you should probably have one other simple kit that uses small parts under
> your belt before starting one of this complexity). The stage by stage, build
> and troubleshoot as-you-go approach makes the job very straightforward.
> --
> chuck
> Chuck Murcko The Topsail Group West Chester PA USA
> chuck@topsail.org
>
> --
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