Which are all reasons why I have never had any interest in owning one.
My experience is limited to repairing maybe 5 and converting 6 to 6M
monobanders where they have a better chance of reliability.
Carl
KM1H
----- Original Message -----
From: "kingwood" <k5jv@kingwoodcable.com>
To: "Amp Reflector" <amps@contesting.com>
Sent: Tuesday, October 20, 2009 6:07 PM
Subject: [Amps] {Collins} 30S-1
> Greetings to all,
>
> There is some misinformation being passed out here about these
> tubes. There are two common 4CX1,500 tube types, the "A", and the "B".
> The
> "A" tube has a 25 watt grid dissipation rating but will not work in the
> 30S-1 without changing the tube socket. The "B" tube has a 1 (one) watt
> grid dissipation and will directly replace a 4CX1,000 in a 30S-1 amp. As
> I
> said in an earlier post, this is a X 10 increase in grid dissipation over
> a
> 4CX1,000.
> .
> It is important to know, and understand, that the band switch in
> the
> 30S-1 was never intended to see more than about 600 watts of RF. This amp
> was designed at a point in time when US Amateurs were only allowed to run
> 1,000 watts AVERAGE INPUT power, not OUTPUT. This band switch is made on
> a
> thin sheet of G10 fiberglass with contact points riveted on. My point is,
> be careful how you handle this switch, both power applied and switching.
> I
> had to pay $500 for the last one I changed out for an RTTY operator. In
> my
> opinion, the 30S-1 should never be operated on any continuous mode. High
> speed CW is also very hard on it.
>
> Despite the other numerous faults with this amp, it is still around
> and quite a topic of conversation. Ask yourself why has it not increased
> in
> value comparable to other similar amps. If you ever had to maintain a
> "fleet" of these amps, as with the MARS program, you will understand why.
>
> I have a 30S-1 with grid drop-out mod, fused step-start, and
> 4CX-1,500 with increased screen voltage. With these mods, it runs
> reliably
> in SSB but I still cringe every time I turn it on -- so many more bad
> things, than good things, can happen every time it is turned on.
>
> 73 de Lon, K5JV
>
> 1110 Golden Bear Ln.
> Kingwood, TX 77339
>
> 281-358-4207
> 281-358-4234 FAX
> 281-795-1335 CELL
>
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