Saturday, November 17, 2018

2M-CD -- Amateur VHF Circular Dipole Antenna

Saw this item advertised on the Amateur Radio Swap Canada Facebook group. The creator is Canadian based out of Lakeshore Ontario. 

VHF Loop - Very Small Transmitting Loops -

His first product was a magnetic loop for 6m which has recently been updated to add a standard tripod mount at the base and different configuration of the teflon tuning screws. Good deal for 6m enthusiasts at $120 US.

His second product that he just launched is what caught my eye, an indoor bookshelf 2m circular dipole that doesn't require a ground plain.

Sellers description

Here is a 2 meter 144-148 MHz circular folded dipole, capable of 100 watts, which is a very compact antenna, requiring no ground plane, small foot print and ideal as a “bookshelf” indoor antenna for those who are restricted in their ability to put an antenna outdoors, or who want to remain stealth. 

I'm really looking forward to trying it out.

More pictures from his website of the antenna.

Saturday, November 03, 2018

Where The Bonus Went - Heil Pro 7 Headset

If you've visited my shack you may have noticed a few Heil Sound brand amateur radio accessories including a couple microphones, rig adapter cables, microphone boom, shock mount, etc.

In September of 2018 I was asked by my employer to work an extra job to help during a changeover between an old contractor and the new contractor who typically do that work. Without going into detail I still had to do my regular job as well so it made for a busy month and a fair bit overtime.

At the end of the project those of use who did the extra work were told we might get a bonus for the work. We joked that a trip to Vegas would be nice but were surprised when the bonus was cash (thanks you to my manager and the upper management for approving that).

Fast forward to yesterday when the bonus showed up on my latest paycheck. I was ready and prepared after having weeks to research & find the item that I wanted to spend it on.

If you've followed my blog you know that I don't typically spent my disposable income on the hobby, with most of my spare income going to family needs like vehicle & household repairs. Instead I use cash from Birthdays and Christmas, or Bonuses like this one. So when I do get some cash to invest in the hobby I try and look for excellent quality items that will hopefully last me for years.

Thus the new purchase is the Heil Pro 7 headset (boomset). I'm currently waiting for delivery in the coming week (as long as the Canada Post rolling job actions doesn't interrupt regular delivery).

I did a ton of research on this item and have high hopes it's a great headset. I have a couple other sets of Hi-Fi stereo headphones from premium brands like Focal, so when it comes to headphones I have some experience and big expectations. It will be very interesting using a headset optimized for amateur radio for the first time.

The Heil Pro 7 has the following features.

  • Generating Element: Dynamic iC
  • Frequency Response: 100 Hz – 12 kHz
  • Polar Pattern: Cardioid
  • Impedance: 600 Ohms
  • Output Level: -57 dB at 1 kHz
  • Weight: 17 oz
  • 2″ thick gel foam ear pads provide extreme comfort for extended periods of time while exhibiting passive noise reduction rated at -26dB, ideal for use in high ambient noise environments.
  • Using technology Bob Heil learned from Paul Klipsch back in the early 70’s, the ear cup enclosures were tuned to the free air cone resonance of the speaker cone thus providing very low distortion with maximum voice articulation providing the ultimate sound reproduction for communications. 
  • The exclusive Heil Phase Reversal system (HPR) allows you to acoustically move the signals forward and creates a spatial widening of the sound field. This feature makes it easier to pull a weak signal from a pileup – useful for DxPeditions and contests as well as a stress reliever as your change the phase angle of the program source.
  • A speaker balance control allows preferred level between the speakers. The balance control located on the LEFT speaker, controls only the left speaker. Begin by setting a comfortable right side speaker level with the AF gain of the receiver. You then adjust the left side speaker where necessary to balance the audio between the speakers. In most cases the balance control will be close to or maximum.
  • The latest version of the Pro 7 features a monitor jack. The monitor feature allows a second operator to plug in headphones to the Pro 7 to monitor audio.

The Pro 7's are available in black, red, blue or pink finishes and includes the following accessories:

  • PTT Switch.
  • Military grade straight cable.
  • Military grade coiled cable.
  • Extra set of ear pads.
  • Washable cotton ear pad covers.

The PRO 7 has an interchangeable microphone system, which allows the microphone element to be easily changed in the field for different types of applications.

  • The low distortion included Dynamic HC-7 (black) element exhibits a frequency response of 100 Hz – 12 kHz with the -3dB points at 100 Hz and 12 kHz. The traditional Heil speech articulation rise is centered at 2K -4KHz with properly balanced highs and lows. The impedance is 600 ohm. The HC-7 is one of our best microphone elements for speech articulation.
  • For the serious contest/DX operators they can upgrade to the HC-74 (orange), which is a redesign of the popular HC-4 element. This element is sold separately. It rolls off the low end at 600 Hz with a 10 dB rise at 2500-3000 Hz, which creates a very articulate signal to break through pileups. 

HC-7 Replaceable Mic Element (included with purchase)
HC-7 Frequency Graph

HC-74 Interchangeable Mic Element (optional purchase)

HC-74 Frequency Graph