• FDIM 2016 - Four Days In May

    'Four Days In May' is the annual convention of the QRP Amateur Radio Club International. It is held in Dayton OH and runs in parallel with the famous Dayton Hamvention. 
  • FDIM Seminars

    Held on Thursday 19th May 2016. Six presentations from well known names in the QRP community. This event attracts an audience of around 400 QRPers.
  • Hamvention Buses

    Visitors to FDIM have an easy journey to the Dayton Hamvention. On Friday and Saturday we have buses running from the hotel door to the Hamvention entrance.
  • Midnight Mischief

    Midnight Mischief at FDIM 2014 ! Guardians of the Sacred Holy Relic open the arc in preparation for the Tuna-Tin MoJo Ceremony. Yes, really !
  • Buses to Hamvention

    Shuttle buses to the Hamvention on Friday and Saturday ($15 for both days) Wilbur Dahmer will guarantee that you have an entertaining ride to the Hara Arena !
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FDIM Registration

Four Days In May (FDIM) - the biggest and best QRP event in the World !
Held each May, it starts the day before the famous Hamvention in Dayton, Ohio and runs for 4 days

A day of seminars (including a free kit), a Buildathon, a Vendors night, an Evening Lecture, a Pizza Night, a QRP Club night, homebrew competitions, games, music, raffles, door prizes, QRP Hall of Fame induction, a Grand Banquet . . . and buses direct to and from the Hamvention.

Seminar tickets (including printed Proceedings, refreshments and a kit to build)  - $41

Banquet tickets  - $36

Live Video Stream

The seminars will not be streamed or recorded this year

Online Registration

Online registration is now closed.

Having sold out of Banquet tickets we have added a few extra seats. 
There are about 20 seminar & banquet tickets available for walk-ins  -  no guarantee, just get there early !

Send an email to This email address is being protected from spambots. You need JavaScript enabled to view it. if you have any queries

FDIM Seminars

Thursday 19 May 2016
8.15am - 5.15pm

  • Opening Address (8.15am)
  •     Welcome to FDIM !
  • Eric Swartz, WA6HHQ (8.20am)
    Elecraft - Shrinking the Multi-Mode HF Transceiver

  • Scott Cowling, WA2DFI (9.00am)
    Zoltan Doczi, HA7DCD 
    WSPR and the Raspberry Pi

  • Guy Hamblen, N7UN (10.00am)
    2016 - The Year of the Portable Operator
    From IOTA to SOTA to NPOTA
  • Paul Darlington, M0XPD (11.15am)
    Occam's Scrip -
    the minimalist measurement mindset
  • Mike Bryce, WB8VGE (2.00pm)
    Troubleshooting and Repair Techniques
  • Grayson Evans, TA2ZGE/KJ7UM (3.15pm)
    Thermatron Homebrew Ideas and Techniques
  • Rex Harper, W1REX (4.15pm)
    The Worlds' Biggest Buildathon

    Includes a 20m transmitter kit to build at the seminar. No tools required !

Tea breaks at 11.00am and 3.00pm
Lunch break at 12.15pm


Rex Harper, W1REX

Friday 20 May 2016
3.30pm - 8.00pm

Once again the Buildathon will be hosted by Rex Harper W1REX !

This year Buildathon will be held on Friday afternoon/evening. Start time is flexible to cater for those returning from the Hamvention. You can start your project between 3.30pm and 5.30pm. It ends at 8.00pm but will probably continue until everyone has completed their project.

The Buildathon is a group build of a small project that can be completed in around 2 - 3 hours (depending on experience). Beginners are particularly encouraged and there will be plenty of people around to help.

This year the project will be to build a keyer with built in paddles

Anyone can participate in Buildathon but space is limited - there are only 35 places !

Register at the QRPme website. The cost is $35, this includes the project kit, elmering during the Buildathon AND the now infamous Buildathon Pizza Party at 5.30pm !


Hamvention Buses

Hamvention Buses

Buses will run from the hotel door to the Hamvention entrance on Friday and Saturday.

This service makes it really easy to get to and from the Hamvention. If you drive you are likely to pay just as much in parking fees and be faced with a long walk to the Hara Arena.

On the outbound route buses will be available from 7.00am until 9.30am. Pickup is at the main entrance of the Holiday Inn.

Return journeys will run from 3.30pm until 5.30pm - your driver will agree a pickup location. Be sure to listen and be at the pickup point no later than 5.30pm

Ticket prices will be confirmed later ($15 for past 3 years). Each ticket will cover outbound/return journeys on both Friday and Saturday.

You can buy your ticket at the hotel during Wednesday evening registration and throughout the Thursday events.

More about :

Grand Banquet

Bruna Begali presents a paddle

Saturday 21 May 2016
7.30pm - 10.00pm

The FDIM Grand Banquet is the last major event of the weekend. There's a great meal, a few announcements, the QRP Hall of Fame induction, results of the homebrew competitions and then a lot of prize giving !

Prizes are donated throughout the FDIM event - we usually have more than 50 and the value may be in excess of $10,000 !


Vendor Night

Vendor table at FDIM

Thursday 19 May 2016
8.00pm - 10.00pm

Vendor Night is free of charge !

Vendors and QRP clubs from around the World will be selling kits, components, antennas and all kinds of goodies.

This is a great place to buy. The vendors have time to chat and you can take your purchases back to the hotel room. For customers, doors open at 8.00pm

Vendors at FDIM 2016 include -

  • Brad Thompson, AA1IP
  • Elecraft
  • Dan Romanchik, KB6NU
  • DX Engineering
  • Four State QRP Group (4SQRP)
  • Kanga UK
  • Kanga USA
  • LNR Precision
  • Pro Audio Engineering
  • QRPme

Book a Table

QRP Club Night

Club Night Button

Friday 20 May 2016
8.00pm - 10.00pm

QRP Club Night is free of charge !

A night of fun, games and socialising. We tried this the last three years and it was a great success.

QRP Clubs and groups will have a table to promote themselves. Tables can be decorated with flags and banners. Flyers and badges can be distributed - and new members recruited.

Each Club can make their table 'their own' but we suggest that some snacks/nibbles/sweets from their area are provided and some kind of game or competition is hosted (think along the lines of toroid winding and left footed CW).

Please - find out who is the lead person for this from your own club. If no one is doing it, then take the lead yourself and contact your fellow club/group members !

Clubs at FDIM 2016 -

  • Austin TX QRP Club
  • Four State QRP Group (4SQRP)
  • Lafayette QRP Group

First Time at FDIM ?

Visiting FDIM for the first time ?
Here's a guide so you know what to expect . . .

More about :

Spouse Activities

Stitching at FDIM

For several years we have set aside rooms for spouses to enjoy some non-radio related activities.

Details will be available later - meet up around 9.00am
No formal activities planned so far

FDIM 2016 Schedule

Venue:  Holiday Inn, Fairborn OH   (map)

 Wednesday 18th May 2016

Registration opens (7.30pm)
Pick up Badge and Proceedings Book,
meet old friends and make new ones !

Thursday 19th May 2016

Registration opens (7.15am)
Seminars (8.15am - 5.15pm)
     Eric Swartz, WA6HHQ
     Scott Cowling, WA2DFI
     Zoltan Doczi, HA7DCD
     Guy Hamblen, N7UN
     Paul Darlington, M0XPD
     Mike Bryce, WB8VGE
     Grayson Evans, TA2ZGE/KJ7UM
     Rex Harper, W1REX

Vendor Evening (8pm - 10pm)

'Meet the Speakers' (8pm - 10pm)

Friday 20th May 2016

Buses to Hamvention (7.00am - 9.30am)
Buses back to hotel (3.30pm - 5.30pm)

Buildathon (3.30pm - 8.00pm)
QRP Club Night (8pm - 10pm)
Show and Tell (8pm - 10pm)
Homebrew Competition (8pm - 10pm)

Saturday 21st May 2016

Buses to Hamvention (7.00am - 9.30am)
Buses back to hotel (3.30pm - 5.30pm)
Grand Banquet, Awards Ceremony
and Door Prizes (7.30pm - 10pm)

Sunday 22nd May 2016

Last visit to Hamvention and home

Events and times are subject to change. Please recheck schedule regularly.


Hotel Rooms

Holiday Inn, FairbornAll FDIM activities take place at the Holiday Inn, Fairborn. 

This is the place to stay to ensure you do not miss any of the action.
We have arranged a special FDIM room rate with complimentary breakfast ($114 + tax)

To book a room you must call  -  937-426-7800
Call Monday to Friday between 8am and 5pm

The group code is 'FDM' - note 3 characters, just 'FDM'

Our group name is  'QRP ARCI FDIM'

Who's Going to FDIM ?

The FDIM Attendee List is updated daily.

There is a line for the person who made the booking - if other people are included in the same party then they will be listed as guest of the person who paid the registration.
If you have booked but are not listed then check that you have a Paypal or Credit Card receipt.

Where is FDIM ?