On Thu, 29 Sep 2005 01:50:01 -0400, SR wrote:
I got a Hammarlund HQ-170. Not the Hammarlund HQ-170A.
A means it has a solid state rectifier instead of the 5u4 high vacuum
rectifier used in the original HQ-170
I am not sure
what the (A) stands for or what is the differences in these models.
The radio is big and it works. I do not have any instructions for it
yet. But I was able to buy a manual, which should come to me sometime soon.
The radio is very sensitive. And it has no speaker. I am using a small
speaker and sometimes headphones. Sometimes it can over power the
speaker and headphones
When I pick up a signal, say a voice, it does not sound as clear. The
sound need to be better clarified. Although I play around with the
buttons, and try to figure out how to better tune in a signal.
Bandwidth is probably set too narrow for AM. HQ170 was designed as an
SSB receiver, so default bandwidth is probably about 2.3Khz, which
will make AM sound like CR*P. Also be careful what you connect to. The
are 3 screws in the back, ground, 3.2 and 500 ohms. The speaker goes
between ground and 3.2 ohm screw.
The radio has no volume button, so I use the NOISE LIMITER button and RF
botton to adjust the volume acordingly.
Has two controls. AF Gain and RF gain. AF gain is the volume control.
There is a AF button but I am not sure what it does. When I bring it up
the signal get stronger.
There is a ANTENNA button, I guess that works like a antenna turner.
Which I also use the MFJ 956. I wonder if I could use them both?
Yes. The front end on the 170 is designed for roughly 100 ohms,
balance or unbalanced. The control is to try to match whatever you
have to the 100 ohms the 170 is looking for
I am not sure what the SLOT/FREG and the SLOT DEPTH buttons are for.
Notch filter. A hole in the passband, you get to decide where it is,
how wide it is, and how deep it is.
The radio has a few terminal screws in the rear. (A, A, G, 6m and SPKR)
I have two alagator clips on A and A and to a PL 259 coax connector then
too my MFJ 956 tuner then to my antenna switcher then to my homebrew 90
feet coil dipole or to my 8 foot fiberglass whip.
the Two A's are for a balanced antenna, such as a folded dipole (300
ohm). SO-239 is for a 50/70 ohm unbalanced antenna like a 1/4 wave
vertical or standard dipole
I have the G (I guess this is for gound), on a clamp and to my radiator
pipe.
Radiatior pipes often make poor Radio Frequency grounds. Metalic cold
water pipe near inlet, or a 'ground' field (copper radials burried in
the back yard).
6m must be for the 50 MHZ! VHF
SPKR is this for 2 speakers or 1?
1 speaker 3.2 ohm usually,. There is a 500 ohm line output used for
things like Phone patches and VOX.
I plan to find a way to add a rear female coax connector to the back of
the radio so I could better connect it to a PL259 coax.
There should already be an SO239 on the back If not, someone removed
it.
I wonder if their is a way to add a frequency counter to this radio?
YOu can, but it is NOT simple especially. First Local oscaillator is
tuned (unusual these days in a triple conversion receiver), and down
converted to 3035Khz. So local oscillator +/- 3035 Khz is the tuned
frequency.
Conversion from 3035 to 455 is via a crystal oscillator, 455 to 60Hz
is a simple L/C circuit. Not real hard to build a very stable 395Khz
L/C oscillator, especially if you are working from a regulated supply
(one of the funny tubes in the HQ170 will glow white/blue when on.
That is a mercury vapor voltage regulator tube...)
Their is one button missing. Their is a small piece of metal sticking
out under the clock. Is their a way I could set the clock?
Behind the clock their is a rod in the inside and it reaches the back
with a hole. Maybe that is the way to set the clock. Their is another
hole like that on the other side on the SLOT FREQ side. But I do not
see a rod behind it. It their suppose to be one?
Also I notice a few holes in the back and inside a plasic you can turn
with a scew driver. Not sure what that is for.
all manner of coils and transformers that can be adjusted. The basic
ones are usually S-meter Zero.
I hope I could find extra tubes and fused should I ever need them.
And I wonder how others who have this radio feel about it?
73, SR!
Reprints of the instruction book can be purchased from
http://www.radioreprints.com/descriptions/hq170.htm