[Amps] Dentron DTR-2000

[Dudley Hurry]

Mike,

I recently reworked a DTR-2000 amp, although I do not have the amp any
longer here are my observations.

> Q1) I was wondering if some of the other DTR-2000 owners out there might
be
> able to tell me what their input SWRs is like and what it may range on the
> some of the bands.

80 meters -1.5 to 1
17 meters - 3 to 1   (used the rig's internal tuner help)

By the way, the RF choke from RF Parts is a great replacement and solves the
choke issues with the amp.  Sells for about $23..


> Q3) In the SSB position, I noticed the bias on the 8877 is down around
50ma.
> I recall that it used to be around 180ma and I not sure if it changed or
> something else if going on.  What's the experts consensus on where idle
bias
> should be with a meager 2700V B+ on the anode?

The DTR-2000 idled at 50 ma.  So does my other 8877 amps.   I did search the
Eimac Spec. sheet, but could not find any certain idle current for AB2,
cathode driven, just refernce to the 8.2 volts on the cathode via a zener..



Hope this helps,

Thanks and 73's,
Dudley
WA5QPZ
jhurry@austin.rr.com






----- Original Message -----
From: "Mike Krzystyniak" <k9mk@flash.net>
To: <amps@contesting.com>
Sent: Sunday, October 20, 2002 10:58 AM
Subject: [Amps] Dentron DTR-2000


>     I recently pulled my DTR-2000 out of semi retirement and aside from
some
> dust and a little stiffness in the tuning caps she fired up just fine.
>
>     While tuning up for a 20M QSO (driven from my FT-1000 into a dummy
load)
> I noticed the input SWR was not even close to 1:1.  Not that I am
surprised
> by this as this amp has no tuned input so I expected that.  But the SWR
was
> higher than I recall it being and was in the range of  >2:1 and <3:1.
Maybe
> something did break...
>
> Q1) I was wondering if some of the other DTR-2000 owners out there might
be
> able to tell me what their input SWRs is like and what it may range on the
> some of the bands.
>
> Q2) Besides going to a tuned input are there are any methods to help
> stabilize the SWR to something closer to 50 ohms?
>
> Q3) In the SSB position, I noticed the bias on the 8877 is down around
50ma.
> I recall that it used to be around 180ma and I not sure if it changed or
> something else if going on.  What's the experts consensus on where idle
bias
> should be with a meager 2700V B+ on the anode?
>
> Thanks!
>
> Mike   K9MK
>
>
>
>
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