eBay

Up for auction is a working National HRO-60 communications receiver with six coils. This radio is from a collection I'll be auctioning over the next few months.  It has been stored indoors in a smoke free and climate controlled home.   No speaker or manuals are included.

 

The eighteen tube HRO-60 was introduced in 1953 and stayed in production until 1964 making it the last tube HRO receiver.  The 60 is a dual conversion receiver (above 7MHz) with an impressive frequency range spanning 50KHz to 54MHz depending on the installed coil unit.   Two RF stages are employed for superior image rejection.  Variable selectivity is provided via a crystal filter with a phasing control.  A CW oscillator and crystal calibrator are also provided.  Reception modes available are CW, AM and NFM (with optional adapter).  Sensitivity is 1.5uv from 2 to 30MHz.

 

In addition to the four standard coils (A, B, C and D) optional coils AC and AD are included for a total of six coils.   The five coils not in use reside in an original storage box.  

 

The specifications of the included coils are as follows:

     

Type    General Coverage      Band Spread 

 

A           14-30 MHz                27-30 MHz

B           7-14.4 MHz               14-14.4 MHz

C           3.5-7.3 MHz              7-7.3 MHz

D           1.7-4.0 MHz              3.5-4.0 MHz

AC        21.0-21.5 MHz

AD        50-54 MHz

  

The HRO-60 front panel controls are as follows:

 

Limiter (Off 0-10)

AF Gain (AC off 0-10)

Calibrate (100-Off-1000)

CWO (5-0-5)

Phones Jack

Band

Tone

Antenna Trim

Tuning

Oscillator

Dimmer

AVC (On/Off)

Selectivity (Off 1-5)

Phasing (5-0-5)

B+ (Off-On)

Selector (CW, AM, NFM, Phono)

RF Gain (0-10)

 

When testing this receiver I found the original electrolytic 40/40uf @ 500volt can capacitor was dried out and it tested at 14/14uf.  The resulting hum was unacceptable so I replaced it with a modern replacement can capacitor meant for Dynaco amplifiers.  The replacement is 20/20/20/30uf @ 525volts.  I paralleled sections to create a 40/50uf @525volt cap.  The original cap will be included for rebuilding.  Aside from that repair this HRO-60 appears to be original and unmodified.

 

Once clean B+ was delivered the receiver came to life.  I connected a short wire antenna and a speaker and I was able to receive a great many stations.  A short antenna in an electrically noisy basement shop is far from ideal but the National performed above expectations.   Several signals were well above S9. 

 

Unlike many receivers that use a single ended audio stage the HRO-60 has a push pull output stage using a pair of 6V6GTs.  The sound is clear and smooth and does not clip easily.  The output transformer is on the chassis so any conventional speaker may be used.

 

This radio is a joy to operate.  The knobs have a wonderful precise feel perfect for band cruising.  The micrometer dial tuning knob is an engineering tour de force.  It features a zero lash worm drive and an ingenious indicator system to display frequency across the spread band.  As the band is traversed a frequency is displayed in one of five small windows on the knob skirt.  When the knob is rotated the indicated frequency changes but only when a window passes through the 8 o'clock position.   The result is a tuning knob that gives the equivalent of a 12 foot linear dial.  Since the frequency displayed in each window changes individually it remains perfectly centered in its window until that window passes through 8 o'clock.  This system operates without lash or noise of any kind and is truly a pleasure to use.  Mechanical quality of this kind is seldom seen today.

 

Cosmetically, this National is in very good condition with a full set of tubes, tube shields, knobs, feet and a bottom cover.  A few scuffs, scratches and scrapes are evident.  The most prominent of these is a section of paint missing above the dial window.  These cosmetic detractions are consistent with being moved around the shack rather than being due to neglect or improper storage.  A previous owner etched their name and SSN on the rear apron in two places - an unfortunate but common practice.   A shorting bar for the antenna connector was fabricated at some point presumably to replace a missing one.  The coil latches have been compressed along the rear edges with pliers.  Despite these detractions, this HRO-60 is on the whole quite presentable and has fared far better than many.  See pics for more details.

  

This receiver is in original, unmodified and unrestored condition.  As with all vintage electronics performance could be improved with a full restoration and alignment.   The age of this radio combined with the fact that it is still working well is a testament to its superior design and the high quality of workmanship throughout.  A new receiver may have more bells and whistles but if you want a band cruiser that will last a lifetime look no further.  

 

Give it a good home!

 

If you have any questions please ask!    

 

Happy Bidding!

 

Payment is expected within 5 days of auction close. I ship only via services listed in the shipping calculator. Shipping costs are the responsibility of the high bidder. This radio will be shipped in a bag, carefully packed and double boxed.  Due to the size and weight of this radio and the need to ship it safely a $20 materials cost is included in the shipping cost displayed by the calculator.  Any shipping over charge greater than one dollar will be refunded.  Also, because of its size and weight, this radio is only offered for sale to bidders in the US.  Thanks for looking!