[Milsurplus] RAL design defect

[wf2u at starband.net]

Mine too... I can't tell the detector going into the regen region unless
listening to CW and I start hearing the tone. Otherwise have to use the
regen test button and listen to the pop to verify it's there.

73, Meir WF2U
Landrum, SC

> On 25 Sep 2006 at 12:43, W7QHO at aol.com wrote:
>
>> In a message dated 9/25/06 9:17:46 AM, rbrunner at gis.net writes:
>>
>>
>> > I've been enjoying my RAL, hearing everything, but thought it
>> excessively noisy.  When the detector goes into regeneration it
>> sounds like a mighty waterfall when it should be barely noticable. 
>
> Hmmmm....mine never sounded like that. Very quiet, in fact. Boy! You
> sure have had some weird problems with your RAL.
>
>> Hmmm...   In my RAL hear a definite "rushing" sound at the
>> regeneration point which becomes a "plop" if one crosses the
>> threshold quickly.   No "mighty waterfall" effect though.
>
> Same thing for me. The receiver is very quiet, and has plenty of gain.
> The only way I can hear the "plop" is if I swing the regen control
> very fast through that point. Otherwise, it goes into and out of
> regeneration
>  so quietly it is sometime difficult to tell.
>
>> Have found my set to be somewhat short on audio gain.   Maybe I need
>> to check into that.
>
> Yes, I agree. Maybe your limiter stage is acting up.
>
> I used an RAL-7 as my main station receiver for many years, and have
> another one now. I use headphones exclusively with it. It has plenty
> of audio gain for me. In fact, the audio stage runs wide open all the
> time.
>  The "gain" control is actually an RF gain control. I always felt that
> my  RAL-7s needed an audio gain control. It is actually pretty easy to
> add,  but the control ends up in a weird place: high and to the right
> of the dial  window.
>
>> What are others hearing?
>
> 1) No waterfall sound at all. Very quiet and sensitive receiver
>
> 2) Plenty of audio gain when used with headphones (for which they
> were designed).
>
> 3) Regeneration is so quiet it is sometimes difficult to tell whether
> it is in  that condition or not. Thus the front-panel push-button
> switch.
>
> 4) Sensitivity compares very favorably with modern receivers.
>
> In fact, my RAL-7 hears everything my restored HW-101 does, and the
> HW-101's measured sensitivity is around 0.1 microvolt for MDS
> according to my HP-8640B.
>
> However, I don't really believe that the 0.1 microvolt figure is
> accurate,  since I KNOW I have leakage somewhere.
>
> Still, I hear band-noise up through 23 Mhz with the RAL-7 whenever I
> connect any wire to the antenna connector, even one only about 6 feet
> long.
>
> And the way I figure it is if the identical setup is used with
> whatever receiver I test, at least the COMPARISON is more likely to be
> valid.
>
> YMMV.
>
> Ken Gordon W7EKB / WC2XSR
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