Lowe HF150 alignment
 

Does anybody have alignment notes on this receiver. Another eBay special
that was "working perfectly, but as is". I need to know how to set the
carrier injection frequency of the BFO. LSB injection is at the edge of the
I.F. passband, resulting in not being able to demodulate these signals. I
did adjust the reference oscillator while in the test mode, so that part is
ok.
According to the schematic, it appears that the reference oscillator is
divided by N so arrive at the carrier injection frequencies but I am not
sure. It could also be an I.F. filter that has developed an assymmetrical
response. Another thing could be that the 2nd LO is off frequency, but since
the BFO is injected at the 455kHz I.F. this is highly unlikely.
Anybody have any experience with this type of situation?

Pete

Another thing............I have already e-mailed Lowe UK...............not
sure what will turn up. Unfortunately, not technical support in the form of
purchased documentation and parts are available to folks in the USA. Some
sort of insurance liabilities, so I am really stuck.

Pete

"Pete KE9OA" wrote in message
...
Does anybody have alignment notes on this receiver. Another eBay special
that was "working perfectly, but as is". I need to know how to set the
carrier injection frequency of the BFO. LSB injection is at the edge of
the I.F. passband, resulting in not being able to demodulate these
signals. I did adjust the reference oscillator while in the test mode, so
that part is ok.
According to the schematic, it appears that the reference oscillator is
divided by N so arrive at the carrier injection frequencies but I am not
sure. It could also be an I.F. filter that has developed an assymmetrical
response. Another thing could be that the 2nd LO is off frequency, but
since the BFO is injected at the 455kHz I.F. this is highly unlikely.
Anybody have any experience with this type of situation?

Pete

Hello Pete,

alignment instructions for the reference oscillator:

-With the TEST message displayed, press the MODE button. Connect a
frequency counter to TP2 (Local Osc).

-Adjust TC1 (on the control unit) for a reading of 45.00000 MHz +/- 20 Hz

alignment instructions for the heterodyne oscillator:

-With the TEST message displayed, connect a frequency counter to TP6 (Audio)

-Press the MODE button. Adjust TC2 for a reading of 3234 Hz +/- 10 Hz.

-Press the FAST button. Adjust VR1 for a reading 8 Hz above (3242 Hz)

-Repeat the procedure


My HF-150 (built around 1995) works very well after repeating that
alignment procedure a few times.

73
Arnie

Thank you very much! I went through this alignment procedure and everything
is fine now. I needed to replace the 4569 divider chip on the display board
before I could do the alignment. This chip had a thermal
problem..........after 15 minutes of operation, the BFO injection frequency
would shift about 3kHz. After replacing the chip and going through the
alignment sequency, I have a good HF-150. Thanks again!

Pete

"arniek" wrote in message
...
Hello Pete,

alignment instructions for the reference oscillator:

-With the TEST message displayed, press the MODE button. Connect a
frequency counter to TP2 (Local Osc).

-Adjust TC1 (on the control unit) for a reading of 45.00000 MHz +/- 20 Hz

alignment instructions for the heterodyne oscillator:

-With the TEST message displayed, connect a frequency counter to TP6
(Audio)

-Press the MODE button. Adjust TC2 for a reading of 3234 Hz +/- 10 Hz.

-Press the FAST button. Adjust VR1 for a reading 8 Hz above (3242 Hz)

-Repeat the procedure


My HF-150 (built around 1995) works very well after repeating that
alignment procedure a few times.

73
Arnie

Hi Pete,

if you should need any other information from the HF150 technical manual
just send me an email.

73,
Arnie

Thanks Arnie......................a fellow in England sent me a scanned PDF
of the manual. You know, I've also got an AOR7030, but the HF150 does seem
to have a much better low end response remeniscent of the old Philco console
radios.
Thanks again!

Pete

"arniek" wrote in message
...
Hi Pete,

if you should need any other information from the HF150 technical manual
just send me an email.

73,
Arnie