[Top] [All Lists]

Re: [Amps] QRO 2500DX MARK lll 4CX800

To: "John Bodine" <>, "Amps Amps" <>
Subject: Re: [Amps] QRO 2500DX MARK lll 4CX800
From: "Carl" <>
Date: Thu, 4 Apr 2019 20:32:11 -0400
List-post: <>
Turn down WHAT a notch? I ask a simple question to clarify the provenance of the tubes and you get your knickers in a knot! Why?

I believe the forum deserves to obtain as much actual data as possible and that comment about the fin area needs further clarification, photos, etc.

If there really is an improved new production version then Im all for it being fully evaluated as a 800W PD tube.

I have mentioned before that my #2 son is in St Petersburg 1-2 times a year with his S.P. girl friend and has obtained other tubes from the factory for me over many years. He is a retired USAF major, speaks, reads, and writes Russian like a native.

If there are really new production GU-74B's I'll see what is involved in getting several included in his luggage for the next visit home. Or see what postage is from Montenegro where they live.


----- Original Message ----- From: John Bodine
To: Carl ; Amps Amps
Sent: Thursday, April 04, 2019 1:56 PM
Subject: Re: [Amps] QRO 2500DX MARK lll 4CX800


I don't have any date codes, as I said before I had great experience with the tubes and DX Engineering. I can tell you this though-the DX engineering tubes are a new cinfiguration underneath heat dissapator fins. As far as backing up my statement, why don't you turn it down a notch, OM.

On Thu, Apr 4, 2019 at 12:06 PM Carl <> wrote:

Can you supply the date codes to backup that statement? My sources state
they are just a later batch released from surplus and the DXE reviews are
mixed....only 3 reviews going back a year or more do not give me a warm

Also DXE is drinking the same Cool Aide as Svetlana which is just one of
many reasons I wont buy anything from them.
The GU-74B is strictly a 600W Pd tube and is also specified for SSB service
in the REAL specs....and not 800W.

Run 'em easy and dont believe the liars and cheats.


----- Original Message ----- From: John Bodine
To: Amps Amps
Cc: ;
Sent: Tuesday, April 02, 2019 7:04 AM
Subject: Re: [Amps] QRO 2500DX MARK lll 4CX800

From personal experience, I would recommend DXengineering for the GU-74b.
These are from a new production run by Svetlana and they work great but YOU
MUST reset the bias when changing tubes or they may not run linear.

On Tue, Apr 2, 2019 at 1:32 AM Steve London <> wrote:

So, Carl, where would you suggest us cheap, constantly crying, hams get new,
at least new-old-stock Eimac 4CX800's and 3CX800's ? Lotsa luck.

Steve, N2IC

On 04/01/2019 09:08 AM, Carl wrote>>
Unlike Eimac, Philips and similar manufactures who design tubes for CCS
service along with plenty of reserve emission to compensate for aging.
tube and most amateur service Chinese are run at the edge.  And cheap
cry constantly.

Amps mailing list


       John Bodine/WU2E

This email has been checked for viruses by AVG.

Amps mailing list


John Bodine/WU2E
Amps mailing list

<Prev in Thread] Current Thread [Next in Thread>